Search

Abstract Objective To evaluate monochorionic diamniotic (MCDA) and dichorionic diamniotic (DCDA) twin pregnancies conceived by assisted reproductive technology (ART) and conceived naturally. Methods We retrospectively analyzed the data on twin pregnancies conceived by ART from January 2015 to January 2022,and compared pregnancy outcomes of MCDA and DCDA twins conceived by ART with those of MCDA and DCDA twins conceived naturally, pregnancy outcomes between MCDA and DCDA twins conceived by ART, and pregnancy outcomes of DCT and TCT pregnancies reduced to DCDA pregnancies with those of DCDA pregnancies conceived naturally. Result MCDA pregnancies conceived by ART accounted for 4.21% of the total pregnancies conceived by ART and 43.81% of the total MCDA pregnancies. DCDA pregnancies conceived by ART accounted for 95.79% of the total pregnancies conceived by ART and 93.26% of the total DCDA pregnancies. Women with MCDA pregnancies conceived by ART had a higher premature delivery rate, lower neonatal weights, a higher placenta previa rate, and a lower twin survival rate than those with MCDA pregnancies conceived naturally (all p

Objective: To evaluate monochorionic diamniotic (MCDA) and dichorionic diamniotic (DCDA) twin pregnancies conceived by assisted reproductive technology (ART) and conceived naturally. Methods: We retrospectively analyzed the data on twin pregnancies conceived by ART from January 2015 to January 2022,and compared pregnancy outcomes of MCDA and DCDA twins conceived by ART with those of MCDA and DCDA twins conceived naturally, pregnancy outcomes between MCDA and DCDA twins conceived by ART, and pregnancy outcomes of DCT and TCT pregnancies reduced to DCDA pregnancies with those of DCDA pregnancies conceived naturally. Result: MCDA pregnancies conceived by ART accounted for 4.21% of the total pregnancies conceived by ART and 43.81% of the total MCDA pregnancies. DCDA pregnancies conceived by ART accounted for 95.79% of the total pregnancies conceived by ART and 93.26% of the total DCDA pregnancies. Women with MCDA pregnancies conceived by ART had a higher premature delivery rate, lower neonatal weights, a higher placenta previa rate, and a lower twin survival rate than those with MCDA pregnancies conceived naturally (all p < 0.05). Women with DCDA pregnancies conceived naturally had lower rates of preterm birth, higher neonatal weights, and higher twin survival rates than women with DCDA pregnancies conceived by ART and those with DCT and TCT pregnancies reduced to DCDA pregnancies (all p < 0.05). Conclusion: Our study confirms that the pregnancy outcomes of MCDA pregnancies conceived by ART are worse than those of MCDA pregnancies conceived naturally. Similarly, the pregnancy outcomes of naturally-conceived DCDA pregnancies are better than those of DCDA pregnancies conceived by ART and DCT and TCT pregnancies reduced to DCDA pregnancies. [ABSTRACT FROM AUTHOR]

Evaluation of relative fetal growth in the form of estimated fetal weight discordance (EFWd) is a necessary element of any ultrasound examination in twin pregnancies. It is one of the criteria for the diagnosis of selective fetal growth restriction (sFGR) according to the most established worldwide guidelines. Apart from the effectiveness of this parameter for the diagnosis of sFGR, it may also be used as an independent factor for risk stratification of neonatal and maternal complications. Furthermore, numerous studies have proven the greater prognostic value of EFWd in dichorionic pregnancies, which may result from differences in the pathogenesis of fetal growth abnormalities in mono- and dichorionic pregnancies. Because of the variability of this parameter throughout pregnancy, there is an ongoing discussion regarding replacing or individualizing it with percentile charts. An additional element, complementary to EFWd in assessing the risk of complications in twin pregnancies is the use of this measurement in combination with Doppler assessment, which increases its predictive value. The use of EFWd as one of the factors influencing care and decision-making in dichorionic twin pregnancies seems to be a simple and effective method, however, further research assessing the use and possible applications of this indicator is necessary. [ABSTRACT FROM AUTHOR]

Objective: To compare morbidity, as measured by length of stay in the neonatal intensive care unit (NICU), in twin and singleton gestations classified as small‐for‐gestational age (SGA) according to estimated fetal weight < 10th percentile on twin or singleton growth charts. Methods: NICU length of stay was compared in 1150 twins and 29 035 singletons that underwent ultrasound assessment between 35 + 0 and 36 + 6 weeks' gestation. Estimated fetal weight was obtained from measurements of head circumference, abdominal circumference and femur length using the Hadlock formula. Gestational age was derived from the first‐trimester crown–rump length measurement, using the larger of the two twins. Singletons and twins were compared in terms of NICU admission rate and length of stay according to classification as SGA by the Fetal Medicine Foundation singleton and twin reference distributions. Results: The overall proportions of twins and singletons admitted to NICU were similar (7.3% vs 7.4%), but twins tended to have longer lengths of stay in NICU (≥ 7 days: 2.4% vs 0.8%; relative risk (RR), 3.0 (95% CI, 1.6–4.4)). Using the singleton chart, a higher proportion of twins were classified as SGA compared with singletons (37.6% vs 7.0%). However, the proportion of SGA neonates entering NICU was similar (10.2% for twins and 10.1% for singletons) and the proportion of SGA neonates spending ≥ 7 days in NICU was substantially higher for twins compared with singletons (3.7% vs 1.4%; RR, 2.6 (95% CI, 1.4–4.7)). Conclusions: When singleton charts are used to define SGA in twins and in singletons, there is a greater degree of growth‐related neonatal morbidity amongst SGA twins compared with SGA singletons. Consequently, singleton charts do not inappropriately overdiagnose fetal growth restriction in twins and they should be used for monitoring fetal growth in both twins and singletons. © 2023 International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

Objective: To derive reference distributions of estimated fetal weight (EFW) in twins relative to singletons. Methods: Gestational‐age‐ and chorionicity‐specific reference distributions for singleton percentiles and EFW were fitted to data on 4391 twin pregnancies with two liveborn fetuses from four European centers, including 3323 dichorionic (DC) and 1068 monochorionic diamniotic (MCDA) twin pregnancies. Gestational age was derived using the larger of the two crown–rump length measurements obtained during the first trimester of pregnancy. EFW was obtained from ultrasound measurements of head circumference, abdominal circumference and femur length using the Hadlock formula. Singleton percentiles were obtained using the Fetal Medicine Foundation population weight charts for singleton pregnancies. Hierarchical models were fitted to singleton Z‐scores with autoregressive terms for serial correlations within the same fetus and between twins from the same pregnancy. Separate models were fitted for DC and MCDA twins. Results: Fetuses from twin pregnancies tended to be smaller than singletons at the earliest gestational ages (16 weeks for MCDA and 20 weeks for DC twins). This was followed by a period of catch‐up growth until around 24 weeks. After that, both DC and MCDA twins showed reduced growth. In DC twins, the EFW corresponding to the 50th percentile was at the 50th percentile of singleton pregnancies at 23 weeks, the 43rd percentile at 28 weeks, the 32nd percentile at 32 weeks and the 22nd percentile at 36 weeks. In MCDA twins, the EFW corresponding to the 50th percentile was at the 36th percentile of singleton pregnancies at 24 weeks, the 29th percentile at 28 weeks, the 19th percentile at 32 weeks and the 12th percentile at 36 weeks. Conclusions: In DC and, to a greater extent, MCDA twin pregnancies, fetal growth is reduced compared with that observed in singleton pregnancies. Furthermore, after 24 weeks, the divergence in growth trajectories between twin and singleton pregnancies becomes more pronounced as gestational age increases. © 2023 International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

Objective The purpose of our study was to evaluate the body mass index (BMI)-specific association between early gestational weight gain (GWG) in dichorionic twin pregnancies and the risk of preeclampsia. Study Design We conducted a retrospective cohort study of all dichorionic twin pregnancies from 1998 to 2013. Data were obtained from a perinatal database and chart abstraction. Prepregnancy BMI was categorized as normal (18.5–24.9 kg/m 2), overweight (25–29.9 kg/m 2), and obese (≥30 kg/m 2). Early GWG was defined as the last measured weight from 16 0/7 to 19 6/7 weeks' gestation minus prepregnancy weight. GWG was standardized for gestational duration using BMI-specific z -score charts for dichorionic pregnancies. Preeclampsia was diagnosed using American College of Obstetricians and Gynecologists criteria and identified with International Classification of Diseases-9 coding. Early GWG z -score was modeled as a three-level categorical variable (≤ − 1 standard deviation [SD], 0, 3 +1 SD), where −1 to +1 was the referent group. We estimated risk differences and 95% confidence intervals (CIs) via marginal standardization. Results We included 1,693 dichorionic twin pregnancies in the cohort. In adjusted analysis, the incidence of preeclampsia increased with increasing early GWG among women with normal BMI. Women with normal BMI and a GWG z -score < − 1 (equivalent to 2.6 kg by 20 weeks) had 2.5 fewer cases of preeclampsia per 100 births (95% CI: −4.7 to − 0.3) compared with the referent; those with GWG z -score > +1 (equivalent to gaining 9.8 kg by 20 weeks) had 2.8 more cases of preeclampsia per 100 (95 % CI: 0.1–5.5) compared with the referent. In adjusted analyses, early GWG had minimal impact on the risk of preeclampsia in women with overweight or obesity. Conclusion GWG of 2.6 kg or less by 20 weeks was associated with a decreased risk of preeclampsia among women pregnant with dichorionic twins and normal prepregnancy BMI. Current GWG guidelines focus on optimizing fetal weight and gestational length. Our findings demonstrate the importance of considering other outcomes when making GWG recommendations for twin pregnancy. Key Points Early GWG decreased with increasing BMI category. Among women with normal weight, as early GWG increased so did the risk of preeclampsia. There was no association between early GWG and preeclampsia among women with overweight or obesity. [ABSTRACT FROM AUTHOR]

Objective: Data are lacking on the impact on pregnancy outcome of the position of the abnormal fetus in a discordant twin pregnancy undergoing selective termination (ST). Tissue maceration post ST of the presenting twin may lead to early rupture of membranes, amnionitis and preterm labor. The aim of this study was to evaluate pregnancy complications and outcome following ST of the presenting vs non‐presenting twin. Methods: This was a multicenter retrospective cohort study of dichorionic diamniotic twin pregnancies that underwent ST due to a discordant fetal anomaly (structural or genetic) between 2007 and 2021. The study population was divided into two groups according to the position of the reduced twin (presenting or non‐presenting) and outcomes were studied accordingly. The primary outcome was a composite of early complications following ST, including infection, preterm prelabor rupture of membranes and pregnancy loss. Results: A total of 190 dichorionic twin pregnancies were included, of which 73 underwent ST of the presenting twin and 117 of the non‐presenting twin. The groups did not differ in either baseline demographic characteristics or mean gestational age at the time of the procedure. ST of the presenting twin resulted in a significantly higher rate of early complications compared with the non‐presenting twin (19.2% vs 7.7%; P = 0.018). Moreover, the rates of preterm delivery (75.3% vs 37.6%; P < 0.001) and neonatal intensive care unit admission (45.3% vs 17.1%; P < 0.001) were higher, and birth weight was lower (P < 0.001), in those pregnancies in which the presenting twin was reduced. Conclusions: ST of the presenting twin resulted in a higher rate of adverse pregnancy outcome compared with that of the non‐presenting twin. These findings should be acknowledged during patient counseling and, if legislation permits, taken into consideration when planning ST. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. A video abstract of this article is available online here. [ABSTRACT FROM AUTHOR]

Abstract Background Twin anemia polycythemia sequence is a rare complication in monochorionic twin pregnancy. Case presentation We describe a case of dichorionic twin pregnancy presenting with suspected twin anemia polycythemia sequence. A 31-year-old White female, on her third pregnancy, had a routine ultrasound scan at 12 weeks gestation, which demonstrated a dichorionic twin pregnancy with one placenta located in the anterior wall and the other in the posterior wall of the uterus. At 21 weeks, a scan demonstrated a 24% growth discordance between the two fetuses with normal Doppler studies and amniotic fluid. At 27 weeks, one twin showed signs of anemia and the other polycythemia; the fetal middle cerebral artery peak systolic velocity was high in the anemic fetus and low in the polycythemic twin (1.8 and 0.5 multiples of the median). An intrauterine blood transfusion was carried out and this increased the fetal hemoglobin concentration in the anemic twin from 3.5 to 12.5 g/dL. At 29 weeks, delivery by cesarean section was carried out because of evidence from middle cerebral artery peak systolic velocity of recurrence of anemia in one twin and worsening polycythemia in the co-twin; at birth the hemoglobin concentrations were 5.6 and 24.9 g/dL, respectively. Histopathological examination confirmed dichorionicity with no communicating vessels between the two placentas. Conclusions This is the first case of twin anemia polycythemia sequence in a dichorionic, diamniotic twin pregnancy where intrauterine blood transfusion was used to prolong the pregnancy by almost 2 weeks in a “twin anemia polycythemia sequence-like” setting.

Abstract Background Both in vitro fertilization (IVF) and preeclampsia (PE) were associated with placental dysfunction. Although IVF can increase the incidence of PE, the pregnancy outcomes and risk factors for preeclampsia in dichorionic twin pregnancies conceived via IVF remain unclear. This study aimed to investigate the pregnancy outcomes and the risk factors for preeclampsia in dichorionic twin pregnancies conceived through IVF compared to those conceived after natural conception (NC). Methods This retrospective observational study enrolled 181 dichorionic twin pregnancy women with preeclampsia from 2016 to 2020. According to the mode of conception, they were allocated into IVF (n = 117) and NC groups (n = 64). The clinical characteristics of preeclampsia and pregnancy outcomes between the two groups were compared by using Student’s t test, chi-square test, and Fisher’s exact test, and logistic regression models were used to obtain adjusted odds ratios (aOR) with 95% confidence intervals (CI) for risk factors of early-onset preeclampsia. Results The incidence of early-onset PE and growth discordance in dichorionic twin pregnancies with PE is significantly higher in IVF-PE group than in NC group (78.60% vs 43.80%, P

Background: Twin anemia polycythemia sequence is a rare complication in monochorionic twin pregnancy. Case presentation: We describe a case of dichorionic twin pregnancy presenting with suspected twin anemia polycythemia sequence. A 31-year-old White female, on her third pregnancy, had a routine ultrasound scan at 12 weeks gestation, which demonstrated a dichorionic twin pregnancy with one placenta located in the anterior wall and the other in the posterior wall of the uterus. At 21 weeks, a scan demonstrated a 24% growth discordance between the two fetuses with normal Doppler studies and amniotic fluid. At 27 weeks, one twin showed signs of anemia and the other polycythemia; the fetal middle cerebral artery peak systolic velocity was high in the anemic fetus and low in the polycythemic twin (1.8 and 0.5 multiples of the median). An intrauterine blood transfusion was carried out and this increased the fetal hemoglobin concentration in the anemic twin from 3.5 to 12.5 g/dL. At 29 weeks, delivery by cesarean section was carried out because of evidence from middle cerebral artery peak systolic velocity of recurrence of anemia in one twin and worsening polycythemia in the co-twin; at birth the hemoglobin concentrations were 5.6 and 24.9 g/dL, respectively. Histopathological examination confirmed dichorionicity with no communicating vessels between the two placentas. Conclusions: This is the first case of twin anemia polycythemia sequence in a dichorionic, diamniotic twin pregnancy where intrauterine blood transfusion was used to prolong the pregnancy by almost 2 weeks in a "twin anemia polycythemia sequence-like" setting. [ABSTRACT FROM AUTHOR]

Background: Both in vitro fertilization (IVF) and preeclampsia (PE) were associated with placental dysfunction. Although IVF can increase the incidence of PE, the pregnancy outcomes and risk factors for preeclampsia in dichorionic twin pregnancies conceived via IVF remain unclear. This study aimed to investigate the pregnancy outcomes and the risk factors for preeclampsia in dichorionic twin pregnancies conceived through IVF compared to those conceived after natural conception (NC).Methods: This retrospective observational study enrolled 181 dichorionic twin pregnancy women with preeclampsia from 2016 to 2020. According to the mode of conception, they were allocated into IVF (n = 117) and NC groups (n = 64). The clinical characteristics of preeclampsia and pregnancy outcomes between the two groups were compared by using Student's t test, chi-square test, and Fisher's exact test, and logistic regression models were used to obtain adjusted odds ratios (aOR) with 95% confidence intervals (CI) for risk factors of early-onset preeclampsia.Results: The incidence of early-onset PE and growth discordance in dichorionic twin pregnancies with PE is significantly higher in IVF-PE group than in NC group (78.60% vs 43.80%, P < 0.001, 11.10% vs 25.00%, P = 0.015). We found that IVF (aOR = 4.635, 95% CI: 2.130-10.084, P < 0.001) and growth discordance (aOR = 3.288; 95% CI: 1.090-9.749, P < 0.05) increased the incidence of early-onset PE.Conclusions: In preeclamptic dichorionic twin pregnancies, IVF and growth discordance were associated with the increased incidence of early-onset PE. The underlying mechanism for the relationship between IVF and early-onset PE or growth discordance may be placental dysfunction. [ABSTRACT FROM AUTHOR]

Introduction: Growth discordancy in dichorionic diamniotic (DCDA) twin gestations is a known complication associated with adverse neonatal outcomes. We aimed to study the differences in placental pathology, in relation to fetal sex, in DCDA twin gestations complicated with growth discordancy.Methods: The medical files of all DCDA twin deliveries complicated by growth discordancy between 2010 and 2020 were reviewed. Growth discordance was defined as a gap between twin birthweights > 20%. A comparison was made between female vs. male growth discordant twins. Placental lesions were classified as lesions related to maternal or fetal malperfusion lesions (MVM, FVM), vascular and villous changes, and inflammatory lesions.Results: Included 174 DCDA twins. Eighty-eight were in the discordant female group and eighty-six in the discordant male group. The groups did not differ in maternal demographics, pregnancy characteristics, and neonatal outcome. The discordant male group had a higher rate of placental MVM lesions as compared to the discordant female group (p = 0.003). The increased rate of placental MVM lesions in the discordant male group compared to the discordant female group did not change whether its co-twin was of similar or opposite sex.Discussion: Higher rate of MVM lesions characterizes growth discordant male neonates in DCDA twin gestations. This finding could represent a different adaptation of male fetuses to a hostile intrauterine environment. [ABSTRACT FROM AUTHOR]

One of the hallmarks of twin pregnancies is the slower rate of fetal growth when compared with singleton pregnancies during the third trimester. The mechanisms underlying this phenomenon and whether it represents pathology or benign physiological adaptation are currently unclear. One important implication of these questions relates to the type growth charts that should be used by care providers to monitor growth of twin fetuses. If the slower growth represents pathology (ie, intrauterine growth restriction caused uteroplacental insufficiency), it would be preferable to use a singleton growth chart to identify a small twin fetus that is at risk for perinatal mortality and morbidity. If, however, the relative smallness of twins is the result of benign adaptive mechanisms, it is likely preferable to use a twin-based charts to avoid overdiagnosis of intrauterine growth restriction in twin pregnancies. In the current review, we addressed this question by describing the differences in fetal growth between twin and singleton pregnancies, reviewing the current knowledge regarding the mechanisms responsible for slower fetal growth in twins, summarizing available empirical evidence on the diagnostic accuracy of the 2 types of charts for intrauterine growth restriction in twin pregnancies, and addressing the question of whether uncomplicated dichorionic twins are at an increased risk for fetal death when compared with singleton fetuses. We identified a growing body of evidence that shows that the use of twin charts can reduce the proportion of twin fetuses identified with suspected intrauterine growth restriction by up to 8-fold and can lead to a diagnosis of intrauterine growth restriction that is more strongly associated with adverse perinatal outcomes and hypertensive disorders than a diagnosis of intrauterine growth restriction based on a singleton-based chart without compromising the detection of twin fetuses at risk for adverse outcomes caused by uteroplacental insufficiency. We further found that small for gestational age twins are less likely to experience adverse perinatal outcomes or to have evidence of uteroplacental insufficiency than small for gestational age singletons and that recent data question the longstanding view that uncomplicated dichorionic twins are at an increased risk for fetal death caused by placental insufficiency. Overall, it seems that, based on existing evidence, the of use twin charts is reasonable and may be preferred over the use of singleton charts when monitoring the growth of twin fetuses. Still, it is important to note that the available data have considerable limitations and are primarily derived from observational studies. Therefore, adequately-powered trials are likely needed to confirm the benefit of twin charts before their use is adopted by professional societies. [ABSTRACT FROM AUTHOR]

Abstract Aims/Introduction The association between gestational diabetes mellitus (GDM) and adverse maternal and perinatal outcomes in twin pregnancies remains unclear. This study was undertaken to highlight risk factors for GDM in women with dichorionic (DC) twins, and to determine the association between GDM DC twins and adverse maternal and perinatal outcomes in a large homogeneous Taiwanese population. Materials and Methods A retrospective cross‐sectional study was carried out on 645 women with DC twins, excluding pregnancies complicated by one or both fetuses with demise (n = 22) or congenital anomalies (n = 9), who gave birth after 28 complete gestational weeks between 1 January 2001 and 31 December 2018. Univariable and multiple logistic regression analyses were carried out. Results Maternal age >34 years (adjusted odds ratio 2.52; 95% confidence interval 1.25–5.07) and pre‐pregnancy body mass index >24.9 kg/m2 (adjusted odds ratio 2.83, 95% confidence interval 1.47–5.46) were independent risk factors for GDM in women with DC twins. Newborns from women with GDM DC twins were more likely to be admitted to the neonatal intensive care unit (adjusted odds ratio 1.70, 95% confidence interval 1.06–2.72) than newborns from women with non‐GDM DC twins. Other pregnancy and neonatal outcomes were similar between the two groups. Conclusions Advanced maternal age and pre‐pregnancy overweight or obesity are risk factors for GDM in women with DC twins. Except for a nearly twofold increased risk of neonatal intensive care unit admission of newborns, the pregnancy and neonatal outcomes for women with GDM DC twins are similar to those for women with non‐GDM DC twins.

Introduction. Multifetal pregnancy is associated with an increased risk of perinatal morbidity and mortality. Type of placentation and discordant fetal growth may be risk factors of adverse pregnancy outcomes.Aim: to compare an impact of dichorionic and monochorionic twin pregnancies with symmetric and discordant fetal growth on perinatal outcomes, as well as morbidity and mortality.Materials and Methods. There was conducted a retrospective study of 485 pregnant women and paired 959 newborns. Depending on the type of chorionicity, subjects were stratified into two study groups being further subdivided into based on describing fetal weight discordance. The antenatal period and the neonatal outcome of newborns in groups and subgroups were compared.Results. We analyzed 308 dichorionic and 177 monochorionic twin pregnancies. It was found that neonate discordant growth was observed in 5.4 % and 13.4 % (p < 0.001), respectively. The incidence of assisted reproductive technologies was higher in dichorionic than in monochorionic twins comprising 66.5 and 40.7 % (р < 0.001). Antenatal mortality in monochorionic vs. dichorionic twins was by 8-fold higher. The preterm birth rate in monochorionic vs. dichorionic twins was 74.6 and 62.7% (p = 0.009), respectively. Neonate body weight in monochorionic vs. dichorionic twins was lowered comprising 1991 and 2430 gr. (р < 0.001), respectively. Low Apgar scores were more common for monochorionic twins with discordant body weight. The rate of early neonatal mortality in monochorionic vs. dichorionic twins was 4.4 % vs. 1.5 % (p = 0.009), whereas in dichorionic vs. monochorionic twins with weight discordance it was up to 5.8 and 10.5% (р < 0.001), respectively.Conclusion. Monochorionic twin pregnancy complicated with growth discordance is associated with a higher risk of adverse antenatal period as well as neonatal morbidity and mortality compared to symmetric DCDA twins. Chorionicity and growth discordancy represent important predictors for outcome of twin pregnancy.

Introduction: Twin pregnancy is associated with an increased risk of perinatal morbidity. Besides, if intrauterine death of a single twin occurs, it increases the morbidity of the surviving co-twin perinatally and postnatally., Aim:  The objective of this study was to determine the incidence of single intrauterine fetal death (SIUFD) in a twin pregnancy and fetal outcome defined in dimensions according to the complications in the surviving co-twin., Material and Methods: Data on twin pregnancies were collected retrospectively for a period of five years (from 2015 to 2019) from the labour room records of the Central Records Department (CRD) at the Postgraduate Institute of Medical Education and Research, Chandigarh, India. Cases with SIUFD were studied individually and neonatal follow-up was taken post delivery for up to three to eight years. Inclusion criteria were SIUFD in twin pregnancies after 14 weeks gestation, chorionicity pre-defined by early trimester ultrasonography. Exclusion criteria were higher-order pregnancy and monoamniotic twins., Results: A total of 1246 (4.273%) twin deliveries were conducted in the study period. Of these, 107 (8.587%) pregnancies had SIUFD with co-twin surviving in utero. Among these, 77 (72%) were dichorionic diamniotic (DCDA) twin pregnancies and 30 (28%) were monochorionic diamniotic (MCDA) twin pregnancies. The incidence of SIUFD was 8.5%. Preterm birth was the most common complication observed in our study and was found in 53.5% and 58.3% of participants in DCDA and MCDA twins, respectively. Early neonatal death (within 24 hours of life) of the surviving twin was found in 29.2% monochorionic twins with SIUFD. SIUFD at < 28 weeks gestation led to a greater number of early neonatal deaths of surviving twins. The incidence of neurodevelopmental disorders (cerebral palsy, developmental delay, epilepsy) in our population after birth was 7.5% (n=93)., Conclusion: Twin pregnancies with SIUFD have an increased incidence of preterm labour, increased neonatal death of the surviving twin, and neurodevelopmental disorders (cerebral palsy, developmental delay, epilepsy). Monochorionicity and SIUFD at <28 weeks gestation are associated with increased neonatal deaths in co-twin. The Incidence of neurodevelopmental disorders is not directly associated with chorionicity, but developmental delay is more profoundly seen in the monochorionic group., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Institutional Ethics Committee, Postgraduate Institute of Medical Education and Research, Chandigarh issued approval INT/IEC/2021/SPL-1085. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Katoch et al.)

Aims/Introduction: The association between gestational diabetes mellitus (GDM) and adverse maternal and perinatal outcomes in twin pregnancies remains unclear. This study was undertaken to highlight risk factors for GDM in women with dichorionic (DC) twins, and to determine the association between GDM DC twins and adverse maternal and perinatal outcomes in a large homogeneous Taiwanese population. Materials and Methods: A retrospective cross‐sectional study was carried out on 645 women with DC twins, excluding pregnancies complicated by one or both fetuses with demise (n = 22) or congenital anomalies (n = 9), who gave birth after 28 complete gestational weeks between 1 January 2001 and 31 December 2018. Univariable and multiple logistic regression analyses were carried out. Results: Maternal age >34 years (adjusted odds ratio 2.52; 95% confidence interval 1.25–5.07) and pre‐pregnancy body mass index >24.9 kg/m2 (adjusted odds ratio 2.83, 95% confidence interval 1.47–5.46) were independent risk factors for GDM in women with DC twins. Newborns from women with GDM DC twins were more likely to be admitted to the neonatal intensive care unit (adjusted odds ratio 1.70, 95% confidence interval 1.06–2.72) than newborns from women with non‐GDM DC twins. Other pregnancy and neonatal outcomes were similar between the two groups. Conclusions: Advanced maternal age and pre‐pregnancy overweight or obesity are risk factors for GDM in women with DC twins. Except for a nearly twofold increased risk of neonatal intensive care unit admission of newborns, the pregnancy and neonatal outcomes for women with GDM DC twins are similar to those for women with non‐GDM DC twins. [ABSTRACT FROM AUTHOR]

Introduction: Large birthweight discrepancy has been identified as a risk factor for perinatal morbidity and mortality in twin pregnancies. However, it remains unclear whether such discordance can be predicted by various biological indices with specific cut‐off values, and how these depend on the gestational age. We aimed to determine the most effective way to predict large birthweight discordance at various gestational ages. Material and methods: A retrospective cohort study of dichorionic twins, live‐born between 2008 and 2018, was conducted. Discordances in biparietal diameter, head circumference, humerus and femur length, abdominal circumference, and estimated fetal weight were calculated—([larger twin − smaller twin] / larger twin) × 100%—and compared between those with and without a large birthweight discordance (≥20%). Receiver operating characteristic curves were constructed to analyze the predictive characteristics of each parameter. Results: Of 598 dichorionic twin pregnancies included, 83 (13.9%) had a birthweight discordance ≥20%. Group differences in biparietal diameter and head circumference discordance were the earliest to emerge (before 20 weeks of gestation), but became insignificant after 36 weeks, followed by humerus and femur length, estimated fetal weight discordance (after 20 weeks), and abdominal circumference discordance (after 28 weeks). The best predictors (with cut‐off values) were discordance in biparietal diameter ≥7.8% at <20 weeks, head circumference ≥4.5% at 20‐23+6 weeks, humerus length ≥4.5% at 24‐27+6 weeks, and estimated fetal weight discordance (≥11.6% at 28‐31+6 weeks, ≥10.5% at 32‐35+6 weeks, and ≥15.0% ≥36 weeks), with sensitivity and specificity of 52%‐77% and 69%‐82%, respectively. Conclusions: Different predictors and cut‐off values may be useful for predicting large inter‐twin birthweight discordance in dichorionic twins at different gestational ages. It is more accurate to use biparietal diameter and head circumference discordance in the early second trimester, humerus length discordance in the late second trimester, and estimated fetal weight discordance in the third trimester. [ABSTRACT FROM AUTHOR]

Objective: To assess, according to chorionicity, the perinatal outcome of twin pregnancy in which vaginal delivery is planned. Methods: JUMODA (JUmeaux MODe d'Accouchement) was a national prospective population‐based cohort study of twin pregnancies, delivered in 176 maternity units in France, from February 2014 to March 2015. In this planned secondary analysis, we assessed, according to chorionicity, the perinatal outcome of twin pregnancies, in which vaginal delivery was planned, that delivered at or after 32 weeks of gestation with the first twin in cephalic presentation. In order to select a population with well‐recognized indications for planned vaginal delivery, we applied the same exclusion criteria as those in the Twin Birth Study, an international randomized trial. Monochorionic twin pregnancies with twin‐to‐twin transfusion syndrome or twin anemia–polycythemia sequence were defined as complicated and were excluded. The primary outcome was a composite of intrapartum mortality and neonatal morbidity and mortality. Multivariable logistic regression models were used to control for potential confounders. Subgroup analyses were conducted according to birth order (first or second twin) and gestational age at delivery (< 37 or ≥ 37 weeks of gestation). Results: Among 3873 twin pregnancies, in which vaginal delivery was planned, that delivered at ≥ 32 weeks' gestation with the first twin in cephalic presentation, meeting the inclusion criteria of the Twin Birth Study, 729 (18.8%) were uncomplicated monochorionic twin pregnancies and 3144 (81.2%) were dichorionic twin pregnancies. The rate of composite intrapartum mortality and neonatal morbidity and mortality did not differ between uncomplicated monochorionic (27/1458 (1.9%)) and dichorionic (107/6288 (1.7%)) twin pregnancies when adjusting for conception by assisted reproductive technologies (adjusted relative risk, 1.07 (95% CI, 0.66–1.75)). No significant difference in the primary outcome was found between the groups on subgroup analyses according to birth order and gestational age at delivery. Conclusion: When vaginal delivery is planned, and delivery occurs at ≥ 32 weeks of gestation with the first twin in cephalic presentation, uncomplicated monochorionic twin pregnancy is not associated with a higher rate of composite intrapartum mortality and neonatal morbidity and mortality compared with dichorionic twin pregnancy. © 2020 International Society of Ultrasound in Obstetrics and Gynecology A video abstract of this article is available online here. [ABSTRACT FROM AUTHOR]

Introduction: The only causal therapy is fetoscopic laser surgery (FLS). The aims of this study were to analyze the long-term outcome of monochorionic twins treated by FLS, including their school career, need for therapy and special aid equipment, and free-time activities, and compare their outcome to matched dichorionic twins.Material and Methods: Among the 57 women treated at a single fetal treatment center between 2008 and 2017 with FLS because of twin-to-twin transfusion syndrome, 25 women with 42 children were included in the FLS group. The control group consisted of 16 dichorionic twin pairs matched for birth year, gestational age (GA), birth weight, and sex. The long-term outcome was assessed by a parental questionnaire and a standardized neurodevelopmental examination for children born before 32 gestational weeks or with a birth weight lower than 1500 g. They were also registered into the Swiss Neonatal Network database. The primary outcome was event-free survival, defined as normal neurology, behavior, vision, and hearing. The secondary outcomes were school career, need for therapy and special aid equipment, and free-time activities.Results: An event-free survival was found in 32 children (76%) in the laser and in 24 children (75%) in the control group (p = 0.91). Neurological anomalies were found in 5 children (12%) in the laser group and 3 children (9%) in the control group (p = 1.00). Multiple logistic regression analysis showed that GA at delivery was the only predictive factor for event-free survival. There were no significant differences regarding school career, therapies, or special aid equipment between the 2 groups. We found that children without FLS were involved in more free-time activities and needed fewer breaks during physical activity than children with FLS during pregnancy.Conclusion: The outcome of monochorionic twins treated with FLS is comparable to the outcome of dichorionic twins. Long-term neurodevelopment in the cohort was mainly dependent on GA at birth. [ABSTRACT FROM AUTHOR]

Objective: To examine the outcomes among discordant dichorionic (DC) twins, where the smaller twin is small for gestational age (SGA) or non-SGA.Materials and methods: We used the national perinatal registry to compare the relationship between selected maternal characteristics (age, parity, body mass index, gestational diabetes, hypertensive disorders, and gestational age at delivery) and neonatal outcomes in discordant >25% DC twins. Chorionicity was established by standard ultrasound criteria and confirmed postpartum. The smaller of the twins was further classified as SGA or non-SGA. The neonatal outcomes included 5-min Apgar score <7, admission to neonatal intensive care unit, early neonatal death and neonatal morbidities.Results: We identified 377 pairs of DC discordant twins >25% born during the 15 years study period, 270 (71.6%) of which included an SGA smaller twin and 107 (28.4%) were non-SGA smaller twin. Maternal characteristics and neonatal morbidities were unrelated to the smaller discordant twin being SGA. A significantly increased incidence of stillbirth was found in the SGA group. Early neonatal deaths were only found in the SGA group.Conclusion: When the smaller twin is SGA, the growth discordant DC twin pair is associated with increased incidence of perinatal deaths. These appear unrelated to maternal characteristics and neonatal morbidity. [ABSTRACT FROM AUTHOR]

Objectives: To examine the performance of the routine 11-13-week scan in detecting fetal defects in twin pregnancies and to examine if, in pregnancies with a fetal defect, compared to those with normal fetuses, there is increased incidence of nuchal translucency thickness (NT) ≥ 95th and ≥ 99th percentiles or intertwin discordance in crown-rump length (CRL) ≥ 10% and ≥ 15%.Methods: This was a retrospective analysis of prospectively collected data in twin pregnancies undergoing routine ultrasound examination for fetal anatomy, according to standardized protocols, at 11-13 weeks' gestation between 2002 and 2019. Pregnancies with known chromosomal abnormality were excluded. The final diagnosis of fetal defect was based on the results of postnatal examination in cases of live birth and on the findings of the last ultrasound examination in cases of pregnancy termination, miscarriage or stillbirth. The performance of the 11-13-week scan in the detection of fetal defects was determined.Results: The study population of 6366 twin pregnancies with two live fetuses at 11-13 weeks' gestation included 4979 (78.2%) dichorionic (DC) and 1387 (21.8%) monochorionic (MC) twin pregnancies. The main findings were: first, the overall incidence of fetal defects was higher in MC than in DC twins (2.8% vs 1.3%); second, the proportion of defects diagnosed in the first trimester was higher in MC than in DC twins (52.6% vs 27.1%); third, the pattern of defects in relation to detectability at the 11-13-week scan (always detectable, sometimes detectable and never detectable) was similar to that reported previously in singleton pregnancies; fourth, always-detectable defects included acrania, alobar holoprosencephaly, encephalocele, pentalogy of Cantrell, exomphalos, body-stalk anomaly, twin reversed arterial perfusion sequence and conjoined twins; fifth, the incidence of fetal NT ≥ 95th percentile was higher in those with than in those without a defect (16.5% vs 4.5% in DC twins and 19.2% vs 5.9% in MC twins) and this was also true for NT ≥ 99th percentile (8.3% vs 1.0% in DC twins and 15.4% vs 2.0% in MC twins); and sixth, the incidence of CRL discordance ≥ 10% was higher in those with than in those without a defect (20.2% vs 7.9% in DC twins and 33.8% vs 9.3% in MC twins) and this was also true for CRL discordance ≥ 15% (10.1% vs 1.9% in DC twins and 28.2% vs 2.8% in MC twins).Conclusions: First, fetal defects are more common in MC than in DC twin pregnancies. Second, first-trimester detection of fetal defects in DC twin pregnancies is similar to that in singleton pregnancies. Third, first-trimester detectability of defects in MC twins is higher than in DC twins. Fourth, in twin pregnancies with a fetal defect, there is higher intertwin discordance in CRL and incidence of increased NT, but the predictive performance of screening by these markers is poor. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Objectives: First, to compare the incidence of single and double fetal death between monochorionic (MC) and dichorionic (DC) twin pregnancies with two live fetuses at 11-13 weeks' gestation and no major abnormalities. Second, to investigate the relationship between gestational age at single fetal death and interval to delivery of the cotwin. Third, to determine the rate of early preterm birth in DC and MC twin pregnancies with two live fetuses and those with single fetal death.Methods: This was a retrospective analysis of prospectively collected data on twin pregnancies undergoing routine ultrasound examination at 11-13 weeks' gestation between 2002 and 2019. The outcome measures, which were stratified by chorionicity, were: first, death of both fetuses at presentation or death of one fetus followed by delivery of a live or dead cotwin within the subsequent 3 days at < 34 weeks' gestation; second, in pregnancies with single fetal death at < 34 weeks' gestation and a live cotwin ≥ 3 days later, the subsequent risk of fetal death and gestational-age distribution at birth of the cotwin; and, third, the gestational-age distribution at birth in pregnancies with two live fetuses.Results: The main findings of this study of 4896 DC and 1329 MC twin pregnancies with two live fetuses at 11-13 weeks' gestation were: first, the rate of death of both twins or death of one fetus and delivery of the live or dead cotwin within 3 days was higher in MC than in DC twin pregnancies; second, the rate of single fetal death with a live cotwin ≥ 3 days later was higher in MC than in DC twin pregnancies, but the rate of subsequent cotwin death in MC twin pregnancies was not significantly different from that in DC twin pregnancies; third, in pregnancies with two live fetuses, the rate of early preterm birth was significantly higher in MC than in DC twin pregnancies; fourth, the rate of early preterm birth in pregnancies with single fetal death and a live cotwin ≥ 3 days later was not significantly different between MC and DC twin pregnancies but the rates were substantially higher than in those with two live fetuses; and, fifth, in both MC and DC pregnancies with single fetal death and a live cotwin ≥ 3 days later, there was a significant inverse association between gestational age at death and interval to delivery (mean interval of 19 weeks for death at 15 weeks and mean interval of 2.5 weeks for death at 30 weeks).Conclusions: First, in MC twin pregnancies, the risk of single or double fetal death is higher than in DC twins. Second, in both MC and DC twin pregnancies, the rate of early preterm birth is higher in those with one fetal death than in those with two live fetuses. Third, in both MC and DC twins with one fetal death, the interval to delivery is related inversely to gestational age at fetal death. These data should be useful in counseling parents as to the likely outcome of their pregnancy after single fetal death and in defining strategies for surveillance in the management of these types of twin pregnancy. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Objective: To investigate the value of increased fetal nuchal translucency thickness (NT) at the 11-13-week scan in the prediction of adverse outcome in dichorionic (DC), monochorionic diamniotic (MCDA) and monochorionic monoamniotic (MCMA) twin pregnancies.Methods: This was a retrospective analysis of prospectively collected data on twin pregnancies undergoing routine ultrasound examination at 11-13 weeks' gestation between 2002 and 2019. In pregnancies with no major defects or chromosomal abnormalities, we examined the value of increased NT ≥ 95th percentile in one or both fetuses in the prediction of, first, miscarriage or death of one or both fetuses at < 20 and < 24 weeks' gestation in DC, MCDA and MCMA twin pregnancies, second, death of one or both fetuses or neonates at ≥ 24 weeks in DC, MCDA and MCMA twin pregnancies, third, development of twin-twin transfusion syndrome (TTTS) or selective fetal growth restriction (sFGR) treated by endoscopic laser surgery at < 20 and ≥ 20 weeks' gestation in MCDA pregnancies, and, fourth, either fetal loss or laser surgery at < 20 weeks' gestation in MCDA pregnancies.Results: The study population of 6225 twin pregnancies included 4896 (78.7%) DC, 1274 (20.5%) MCDA and 55 (0.9%) MCMA pregnancies. The incidence of NT ≥ 95th percentile in one or both fetuses in DC twin pregnancies was 8.3%; in MCDA twins the incidence was significantly higher (10.4%; P = 0.016), but in MCMA twins it was not significantly different (9.1%; P = 0.804) from that in DC twins. In DC twin pregnancies, the incidence of high NT was not significantly different between those with two survivors and those with adverse outcome. In MCMA twin pregnancies, the number of cases was too small for meaningful assessment of the relationship between high NT and adverse outcome. In MCDA twin pregnancies with at least one fetal death or need for endoscopic laser surgery at < 20 weeks' gestation, the incidence of NT ≥ 95th percentile was significantly higher than in those with two survivors (23.5% vs 9.8%; P < 0.0001). Kaplan-Meier analysis in MCDA twin pregnancies showed that, in those with NT ≥ 95th percentile, there was significantly lower survival at < 20 weeks' gestation than in those with NT < 95th percentile (P = 0.001); this was not the case for survival at ≥ 20 weeks (P = 0.960). The performance of screening by fetal NT ≥ 95th percentile for prediction of either fetal loss or need for endoscopic laser surgery at < 20 weeks' gestation was poor, with a detection rate of 23.5% at a false-positive rate of 8.9%, and the relative risk, in comparison to fetal NT < 95th percentile, was 2.640 (95% CI, 1.854-3.758; P < 0.0001). In MCDA twin pregnancies, the overall rate of fetal loss or need for laser surgery at < 20 weeks' gestation was 10.7% but, in the subgroups with NT ≥ 95th and NT ≥ 99th percentiles, which constituted 10.4% and 3.3% of the total, the rates increased to 24.1% and 40.5%, respectively.Conclusions: In MCDA twin pregnancies with no major fetal abnormalities, measurement of NT at the 11-13-week scan is a poor screening test for adverse pregnancy outcome. However, the finding in one or both fetuses of NT ≥ 95th percentile, and more so ≥ 99th percentile, is associated with a substantially increased risk of fetal loss or need for endoscopic laser surgery at < 20 weeks' gestation. The extent to which closer monitoring and earlier intervention in the high-risk group can reduce these complications remains to be determined. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Objective: To investigate the value of intertwin discordance in fetal crown-rump length (CRL) at the 11-13-week scan in the prediction of adverse outcome in dichorionic (DC), monochorionic diamniotic (MCDA) and monochorionic monoamniotic (MCMA) twin pregnancies.Methods: This was a retrospective analysis of prospectively collected data on twin pregnancies undergoing routine ultrasound examination at 11-13 weeks' gestation between 2002 and 2019. In pregnancies with no major abnormalities, we examined the value of intertwin discordance in fetal CRL in DC, MCDA and MCMA twins in the prediction of fetal loss at < 20 and < 24 weeks' gestation, perinatal death at ≥ 24 weeks, preterm delivery at < 32 and < 37 weeks, birth of at least one small-for-gestational-age (SGA) neonate with birth weight < 5th percentile and intertwin birth-weight discordance of ≥ 20% and ≥ 25%.Results: First, the study population of 6225 twin pregnancies included 4896 (78.7%) DC, 1274 (20.4%) MCDA and 55 (0.9%) MCMA twin pregnancies. Second, median CRL discordance in DC twin pregnancies (3.2%; interquartile range (IQR), 1.4-5.8%) was lower than in MCDA twins (3.6%; IQR, 1.6-6.2%; P = 0.0008), but was not significantly different from that in MCMA twins (2.9%; IQR, 1.2-5.1%; P = 0.269). Third, compared to CRL discordance in DC twin pregnancies with two non-SGA live births at ≥ 37 weeks' gestation, there was significantly larger CRL discordance in both DC and MCDA twin pregnancies complicated by fetal death at < 20 and < 24 weeks' gestation, perinatal death at ≥ 24 weeks, preterm birth at < 32 and < 37 weeks, birth of at least one SGA neonate and birth-weight discordance ≥ 20% and ≥ 25%, and in MCDA twin pregnancies undergoing endoscopic laser surgery. Fourth, the predictive performance of CRL discordance for each adverse pregnancy outcome was poor, with areas under the receiver-operating-characteristics curves ranging from 0.533 to 0.624. However, in both DC and MCDA twin pregnancies with large CRL discordance, there was a high risk of fetal loss. Fifth, in DC twin pregnancies, the overall rate of fetal loss at < 20 weeks' gestation was 1.3% but, in the small subgroup with CRL discordance of ≥ 15%, which constituted 1.9% of the total, the rate increased to 5.3%. Sixth, in MCDA twin pregnancies, the rate of fetal loss or endoscopic laser surgery at < 20 weeks was about 11%, but, in the small subgroups with CRL discordance of ≥ 10%, ≥ 15% and ≥ 20%, which constituted 9%, < 3% and < 1% of the total, the risk was increased to about 32%, 49% and 70%, respectively. Seventh, in MCMA twin pregnancies, there were no significant differences in CRL discordance for any of the adverse outcome measures, but this may be the consequence of the small number of cases in the study population.Conclusions: In both DC and MCDA twin pregnancies, increased CRL discordance is associated with an increased risk of fetal death at < 20 and < 24 weeks' gestation, perinatal death at ≥ 24 weeks, preterm birth at < 37 and < 32 weeks, birth of at least one SGA neonate and birth-weight discordance ≥ 20% and ≥ 25%, but CRL discordance is a poor screening test for adverse pregnancy outcome. However, in DC twins, CRL discordance of ≥ 15% is associated with an increased risk of fetal loss at < 20 and < 24 weeks' gestation and, in MCDA twins, CRL discordance of ≥ 10%, and more so discordance of ≥ 15% and ≥ 20%, is associated with a very high risk of fetal loss or endoscopic laser surgery at < 20 and < 24 weeks and this information is useful in counseling women and defining the timing for subsequent assessment and possible intervention. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Objectives: To report and compare pregnancy outcome in dichorionic (DC), monochorionic diamniotic (MCDA) and monochorionic monoamniotic (MCMA) twin pregnancies with two live fetuses at 11-13 weeks' gestation and to examine the impact of endoscopic laser surgery for severe twin-twin transfusion syndrome (TTTS) and/or selective fetal growth restriction (sFGR) on the outcome of MCDA twins.Methods: This was a retrospective analysis of prospectively collected data on twin pregnancies undergoing routine ultrasound examination at 11-13 weeks' gestation between 2002 and 2019. In pregnancies with no major abnormalities, we compared overall survival, fetal loss at < 24 weeks' gestation, perinatal death at ≥ 24 weeks, delivery at < 37 and < 32 weeks, and birth weight < 5th percentile between DC, MCDA and MCMA twins.Results: The study population of 6225 twin pregnancies with two live fetuses at 11-13 weeks' gestation with no major abnormalities included 4896 (78.7%) DC, 1274 (20.5%) MCDA and 55 (0.9%) MCMA twins. In DC twins, the rate of loss at < 24 weeks' gestation in all fetuses was 2.3%; this rate was higher in MCDA twins (7.7%; relative risk (RR), 3.258; 95% CI, 2.706-3.923) and more so in MCMA twins (21.8%; RR, 9.289; 95% CI, 6.377-13.530). In DC twins, the rate of perinatal death at ≥ 24 weeks in all twins that were alive at 24 weeks was 1.0%; this rate was higher in MCDA twins (2.5%; RR, 2.456; 95% CI, 1.779-3.389) and more so in MCMA twins (9.3%; RR, 9.130; 95% CI, 4.584-18.184). In DC twins, the rate of preterm birth at < 37 weeks' gestation in pregnancies with at least one liveborn twin was 48.6%; this rate was higher in MCDA twins (88.5%; RR, 1.824; 95% CI, 1.760-1.890) and more so in MCMA twins (100%; RR, 2.060; 95% CI, 2.000-2.121). In DC twins, the rate of preterm birth at < 32 weeks was 7.4%; this rate was higher in MCDA twins (14.2%; RR, 1.920; 95% CI, 1.616-2.281) and more so in MCMA twins (26.8%; RR, 3.637; 95% CI, 2.172-6.089). In DC twin pregnancies with at least one liveborn twin, the rate of a small-for-gestational-age neonate among all liveborn twins was 31.2% and in MCDA twins this rate was higher (37.8%; RR, 1.209; 95% CI, 1.138-1.284); in MCMA twins, the rate was not significantly different (33.3%; RR, 1.067; 95% CI, 0.783-1.455). Kaplan-Meier analysis showed a significant difference in survival in MCDA and MCMA twins, compared to DC twins, for both the interval of 12 to < 24 weeks' gestation (log-rank test, P < 0.0001 for both) and that of ≥ 24 to 38 weeks (log-rank test, P < 0.0001 for both). Endoscopic laser ablation of intertwin communicating placental vessels was carried out in 127 (10.0%) MCDA twin pregnancies for TTTS and/or sFGR and, in 111 of these, surgery was performed at < 24 weeks; both fetuses survived in 62 (55.9%) cases, one fetus survived in 25 (22.5%) cases and there were no survivors in 24 (21.6%) cases. On the extreme assumption that, had laser surgery not been carried out in these cases, all fetuses would have died, the total fetal loss rate at < 24 weeks' gestation in MCDA twins would have been 13.5%.Conclusions: The rates of fetal loss at < 24 weeks' gestation, perinatal death at ≥ 24 weeks and preterm birth are higher in MCDA and more so in MCMA twins than in DC twins. In MCDA twins, the rate of fetal loss may have been reduced by endoscopic laser surgery in those that developed early TTTS and/or sFGR. These data would be useful in counseling parents as to the likely outcome of their pregnancy and in defining strategies for surveillance and interventions in the management of the different types of twin pregnancy. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Crown-rump length discordance, defined as ≥10% discordance, has been investigated as an early sonographic marker of subsequent growth abnormalities and is associated with an increased risk of fetal loss in twin pregnancies. Previous studies have not investigated the prevalence of fetal aneuploidy or structural anomalies in twins with discordance or the independent association of crown-rump length discordance with adverse perinatal outcomes. Moreover, data are limited on cell-free DNA screening for aneuploidy in dichorionic twins with discordance. This study aimed to evaluate whether crown-rump length discordance in dichorionic twins between 11 and 14 weeks of gestation is associated with a higher risk of aneuploidy, structural anomalies, or adverse perinatal outcomes and to assess the performance of cell-free DNA screening in dichorionic twin pregnancies with crown-rump length discordance. This was a secondary analysis of a multicenter retrospective cohort study that evaluated the performance of cell-free DNA screening for the common trisomies in twin pregnancies from December 2011 to February 2020. For this secondary analysis, we included live dichorionic pregnancies with crown-rump length measurements between 11 and 14 weeks of gestation. First, we compared twin pregnancies with discordant crown-rump lengths with twin pregnancies with concordant crown-rump lengths and analyzed the prevalence of aneuploidy and fetal structural anomalies in either twin. Second, we compared the prevalence of a composite adverse perinatal outcome, which included preterm birth at <34 weeks of gestation, hypertensive disorders of pregnancy, stillbirth or miscarriage, small-for-gestational-age birthweight, and birthweight discordance. Moreover, we assessed the performance of cell-free DNA screening in pregnancies with and without crown-rump length discordance. Outcomes were compared with multivariable regression to adjust for confounders. Of 987 dichorionic twins, 142 (14%) had crown-rump length discordance. The prevalence of aneuploidy was higher in twins with crown-rump length discordance than in twins with concordance (9.9% vs 3.9%, respectively; adjusted relative risk, 2.7; 95% confidence interval, 1.4–4.9). Similarly, structural anomalies (adjusted relative risk, 2.5; 95% confidence interval, 1.4–4.4]) and composite adverse perinatal outcomes (adjusted relative risk, 1.2; 95% confidence interval, 1.04–1.3) were significantly higher in twins with discordance. A stratified analysis demonstrated that even without other ultrasound markers, there were increased risks of aneuploidy (adjusted relative risk, 3.5; 95% confidence interval, 1.5–8.4) and structural anomalies (adjusted relative risk, 2.7; 95% confidence interval, 1.5–4.8) in twins with CRL discordance. Cell-free DNA screening had high negative predictive values for trisomy 21, trisomy 18, and trisomy 13, regardless of crown-rump length discordance, with 1 false-negative for trisomy 21 in a twin pregnancy with discordance. Crown-rump length discordance in dichorionic twins is associated with an increased risk of aneuploidy, structural anomalies, and adverse perinatal outcomes, even without other sonographic abnormalities. Cell-free DNA screening demonstrated high sensitivity and negative predictive values irrespective of crown-rump length discordance; however, 1 false-negative result illustrated that there is a role for diagnostic testing. These data may prove useful in identifying twin pregnancies that may benefit from increased screening and surveillance and are not ascertained by other early sonographic markers. [ABSTRACT FROM AUTHOR]

Objective: To determine if maternal height in nulliparous women influences pregnancy results in twin pregnancies., Material and Methods: Retrospective cohort analysis evaluating twin pregnancies followed at Centro Hospitalar Universitário Lisboa Central, between 1995 and 2020. Of the 2900 pregnancies followed in that period, 886 nulliparous women with dichorionic twin pregnancies were selected. Two groups were considered: A - maternal height <163 cm (

Introduction: The aim of this systematic review was to quantify the association between birthweight discordance and neonatal morbidity in twin pregnancies.Material and Methods: MEDLINE, Embase and Cinahl databases were searched. Studies reporting the occurrence of morbidity in twins affected compared with those not affected by birthweight discordance were included. The primary outcome was composite neonatal morbidity (including neurological, respiratory, infectious morbidities, abnormal acid-base status and necrotizing enterocolitis). The secondary outcomes were the individual morbidities. Sub-group analysis according to chorionicity, gestational age at birth and fetal weight (smaller vs larger twin) was also performed. Random-effect head-to-head meta-analyses were used to analyze the data.Results: Twenty studies (10 851 twin pregnancies) were included. The risk of composite morbidity was significantly higher in the pregnancies with birthweight discordance ≥15% (odds ratio [OR] 1.4, 95% confidence interval [CI] 1.0-1.9), ≥20% (OR 2.2, 95% CI 1.40-3.45), ≥25% (OR 2.5, 95% CI 1.8-3.6), and ≥30% (OR 3.4, 95% CI 2.2-3.2). In dichorionic twins, birthweight discordance ≥15% (OR 2.4, 95% CI 1.65-3.46), ≥20% (OR 2.2, 95% CI 1.3-3.8), ≥25% (OR 2.7, 95% CI 1.4-5.1) and ≥30% (OR 3.6, 95% CI 2.3-5.7) were all significantly associated with composite neonatal morbidity. Analysis of monochorionic twins was hampered by the very small number of included studies, which precluded adequate statistical power. Monochorionic twins with a birthweight discordance ≥20% were at significantly higher risk of composite neonatal morbidity (OR 2.2, 95% CI 1.1-4.9) compared with those presenting with lesser degree of discordance. When stratifying the analysis according to gestational age at birth and fetal size, twins with birthweight discordance ≥15%, 20%, 25% and 30% delivered at ≥34 weeks were at higher risk of neonatal morbidity compared with controls, but there was no difference in the risk of morbidity between the larger and the smaller twin in the discordant pair.Conclusions: Birthweight discordance is associated with neonatal morbidity in twin pregnancies. The strength of this association persists for dichorionic twins. It was not possible to extrapolate robust evidence on monochorionic twins due to the low power of the analysis due to the small number of included studies. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the association between discordance in crown–rump length (CRL) and adverse pregnancy and perinatal outcomes in dichorionic twin pregnancies. This was a retrospective cohort study of dichorionic twin pregnancies after IVF that showed two live fetuses at the first ultrasound scan between 6 +5 and 8 weeks gestational age from 1 January 2015 to 31 December 2016. Study groups were defined by the presence or absence of 20% or more discordance in CRL. The primary outcomes were early fetal loss of one or both fetuses before 12 weeks and birthweight discordance. Secondary outcomes included fetal anomalies, fetal loss between 12 and 28 weeks, stillbirth, small for gestational age (SGA) at birth, low birthweight (LBW), very low birthweight (VLBW), admission to the neonatal intensive care unit (NICU) and preterm delivery (PTD). CRL-discordant twin pregnancies were more likely to end in the loss of one fetus before 12 weeks' gestation (odds ratio [OR] 15.877, 95% confidence interval [CI] 10.495–24.019). Discordant twin pregnancies with twin deliveries had a significantly higher risk of birthweight discordance (OR 1.943, 95% CI 1.032–3.989). There was no significant difference in perinatal outcomes including fetal anomalies, PTD, LBW, VLBW, SGA, neonatal death and admission to NICU between singleton or twin deliveries. Discordant twin pregnancies were at increased risk of one fetal loss prior to 12 weeks' gestation. Except for birthweight discordance, there was no significant difference between CRL discordance and other adverse perinatal outcomes. [ABSTRACT FROM AUTHOR]

Introduction: Intertwin birthweight (BW) difference is associated with an increased risk of adverse outcome. Ultrasound estimated fetal weight (EFW) is the current method to predict intertwin BW difference, however, the sensitivity is poor. Therefore, new methods are needed. Placental T2* estimated by magnetic resonance imaging (MRI) provides non-invasive information about the placental function. This study aimed to investigate placental T2* difference as a new predictor of BW difference, and to compare it to the EFW.Methods: We included 25 dichorionic twin pairs at 19-38 weeks' gestation. Placental T2* was obtained by MRI and EFW by ultrasound. Correlations between each predictor and BW difference were examined by simple linear regression, and the combined model was analyzed by multiple linear regression and likelihood ratio test.Results: Strong positive correlations were demonstrated between intertwin differences in placental T2* and BW (r = 0.80, p < 0.005), and EFW and BW (r = 0.64, p < 0.005). Placental T2* difference was a strong independent predictor of BW difference (p < 0.001), and the combined model performed better than each predictor alone (p < 0.0001).Discussion: This pilot study demonstrates that placental T2* difference may be a predictor of intertwin BW difference irrespectively of fetal size. The clinical potential of this method deserves further investigation in a larger clinical study. [ABSTRACT FROM AUTHOR]

Nonimmune hydrops remains a challenge in the prenatal setting with many cases not having a clear etiology determined prior to birth. We present an unusual case of one fetus of a dichorionic twin pair presenting at 24 weeks' gestation with hydrops and fetal pancytopenia with complete absence of white cells of unknown etiology, as revealed by cordocentesis. Serial red blood cell transfusions resulted in resolution of hydrops and continuation of the pregnancy until 35 weeks' gestation. Pancytopenia was noted throughout gestation and persisted in the newborn period. Moreover, the T-cell receptor excision circle (TREC) assay, a newborn screening test for severe T-cell deficiency, was abnormal at birth. Further evaluation revealed detectable TRECs and normal response to lymphocyte mitogens indicating some preserved thymic and lymphocyte function. The affected child had spontaneous resolution of the pancytopenia, including her severe T-cell deficiency, by 10 weeks of life. There has been no recurrence as of 24 months of age. The self-resolving nature of the pancytopenia is an important feature of this case of nonimmune hydrops. The abnormal TREC assay at birth in the affected infant may help explain the discordant prenatal findings. [ABSTRACT FROM AUTHOR]

Background. A congenital cystic adenomatoid malformation (CCAM) is a foetal pulmonary development abnormality caused by airway dysgenesis that is characterized by cystic or adenomatous lesions in the terminal bronchioles. The size of the mass, the degree of the mediastinal shift, and the presence of hydrops and polyhydramnios can all affect the severity of a case. Treatment can be initiated at early stages by applying prenatal and postnatal methods. Because CCAM is a rare pathology that is often only accidentally diagnosed during routine ultrasounds, we would like to share our case report to enrich the literature on this pathology and to present a case successfully treated at our hospital. Materials and methods. A patient with her first multiple pregnancy was seen for prenatal care and her first ultrasound at 17 weeks of gestation. One of the twins was diagnosed with a congenital cystic adenomatoid malformation of the left lung. At 20 weeks of gestation, an enlarged left lung with small cysts, a compressed right lung, a compressed and displaced heart, and oligohydramnios were observed. At 28 weeks of gestation, a fetoplacental circulation disorder appeared. At 32 weeks of gestation, due the unstable condition of the affected foetus, the twins were delivered via a C-section. The treatment of the newborn included antibiotics, caffeine citrate, and breathing therapy. Results and conclusions. CCAM are often diagnosed by accident when performing routine pregnancy ultrasound examinations. CT is the most reliable X-ray-based examination method for confirming a diagnosis. When CCAM is suspected in the foetus, amniocentesis and cariotype identification are performed, but chromosomal anomalies related to CCAM are often not identified. Currently, the best treatment results have been achieved by applying combined prenatal therapy and early surgical treatment.

Objective: To compare placental histopathological lesions and pregnancy outcomes in singleton and twin pregnancies complicated by preeclampsia (PE).Methods: Maternal characteristics, neonatal outcomes, and placental histopathology reports of pregnancies complicated by PE between January 2008 and October 2016 were reviewed. Results were compared between singletons (singleton group) and dichorionic-diamniotic twins (twin group). Placental lesions were classified into maternal and fetal vascular supply lesions. Small for gestational age (SGA) was defined as birth weight ≤10th percentile. Composite adverse neonatal outcome was defined as one or more early neonatal complications.Results: Compared to the twin group (n = 67), the singleton group (n = 275) was characterized by lower maternal age (p = 0.003), higher gestational age (p < 0.001), higher rates of previous PE (p = 0.017), chronic hypertension (p = 0.036), and severe features (p < 0.001). Placentas from the singleton group were characterized by higher rates of maternal vascular malperfusion lesions (p < 0.001) and fetal vascular supply lesions (p = 0.002). Using multivariable regression analysis, composite maternal and fetal vascular malperfusion lesions were independently associated with singletons (aOR = 2.7, 95% CI = 1.2-7.8, p < 0.001, and aOR = 1.2, 95% CI = 1.2-5.6, p = 0.025, respectively). SGA was more common in the singleton group (p = 0.002). Neonatal outcome did not differ between the groups.Conclusion: Placentas from singleton pregnancies complicated by PE were characterized by higher rates of maternal and fetal vascular lesions compared to those from twin pregnancies, suggesting that different mechanisms participate in the development of PE in these two groups. [ABSTRACT FROM AUTHOR]

Objective: To assess the clinical characteristics of fetal aneuploidy between dichorionic twins (DCT) and monochorionic twins (MCT) undergoing invasive prenatal diagnosis.Methods: Twin fetuses undergoing invasive prenatal diagnosis were enrolled in this study. All twin fetuses were classified into 2 groups according to chorionicity. The rates of fetal aneuploidy in different groups were compared.Result: This study included 1,714 fetuses (857 sets of twin pairs); among them, 1,190 were DCT and 524 were MCT. Overall, the rate of aneuploidy was 4.7% (56/1,190) in DCT and 3.4% (18/524) in MCT. Sixty-four (86.5%, 64/74) fetal aneuploidies occurred in only one fetus of the twin pairs. In DCT, the most common aneuploidy was trisomy 21 (53.6%, 30/56), followed by trisomy 18 (21.4%, 12/56) and trisomy 13 (8.9%, 5/56), while in MCT, the most common aneuploidy was Turner syndrome (33.3%, 6/18), followed by trisomy 21 (27.7%, 5/18) and 47,XYY (11.0%, 2/18).Conclusion: Aneuploidy mostly occurred in only one fetus in the twin pairs. The most common aneuploidy was trisomy 21 in DCT and Turner syndrome in MCT. Dual amniocentesis should be performed when discordant monozygotic twins are suspected. [ABSTRACT FROM AUTHOR]

Background. A congenital cystic adenomatoid malformation (CCAM) is a foetal pulmonary development abnormality caused by airway dysgenesis that is characterized by cystic or adenomatous lesions in the terminal bronchioles. The size of the mass, the degree of the mediastinal shift, and the presence of hydrops and polyhydramnios can all affect the severity of a case. Treatment can be initiated at early stages by applying prenatal and postnatal methods. Because CCAM is a rare pathology that is often only accidentally diagnosed during routine ultrasounds, we would like to share our case report to enrich the literature on this pathology and to present a case successfully treated at our hospital. Materials and methods. A patient with her first multiple pregnancy was seen for prenatal care and her first ultrasound at 17 weeks of gestation. One of the twins was diagnosed with a congenital cystic adenomatoid malformation of the left lung. At 20 weeks of gestation, an enlarged left lung with small cysts, a compressed right lung, a compressed and displaced heart, and oligohydramnios were observed. At 28 weeks of gestation, a fetoplacental circulation disorder appeared. At 32 weeks of gestation, due the unstable condition of the affected foetus, the twins were delivered via a C-section. The treatment of the newborn included antibiotics, caffeine citrate, and breathing therapy. Results and conclusions. CCAM are often diagnosed by accident when performing routine pregnancy ultrasound examinations. CT is the most reliable X-ray-based examination method for confirming a diagnosis. When CCAM is suspected in the foetus, amniocentesis and cariotype identification are performed, but chromosomal anomalies related to CCAM are often not identified. Currently, the best treatment results have been achieved by applying combined prenatal therapy and early surgical treatment. [ABSTRACT FROM AUTHOR]

Objective: To evaluate if inter-twin estimated fetal weight (EFW) differences at 21-24 weeks scans predict birth weight discordance in monochorionic and dichorionic twins born at three gestational age periods. Methods: We counted the number of pairs with discordant EFWs (EFWs greater than the mean + 1SD; i.e. a difference above 12% in dichorionic and 21% in monochorionic twins) derived during a 21-24 weeks' scan as compared to actual discordant birth weight (>25%) in monochorionic and dichorionic pairs born at ≤32, 33-36 and >36 weeks. Results: We studied 416 dichorionic and 244 monochorionic twins. The frequency of EFWs discordance at 21-24 weeks was the same for dichorionic and monochorionic twins but the total number of birth weight discordant pairs was significantly smaller among dichorionic twins (OR 0.2, 95% CI 0.1, 0.6). Generally, the positive predictive values for birth weight discordance by using the EFWs difference were quite poor, but always better in monochorionic than in dichorionic twins. Whereas the negative predictive value and hence the sensitivity for monochorionic twins was 100% irrespective of gestational age at birth, it was much lower in the dichorionic pairs. Conclusion: Concordant EFWs at 21-24 weeks exclude discordant birth weight in monochorionic twins whereas discordant EFWs are poor predictors of birth weight discordance especially in dichorionic twins irrespective when the twins were born. [ABSTRACT FROM AUTHOR]

Background/objectives: Multiple pregnancies have tripled in the United States over the past 3 decades. Attributed to increasing maternal age at delivery but more so assisted reproductive technological advances, an effort has been made to decrease twinning through elective single embryo transfer. We sought to review and evaluate risks of monochorionic twinning as a predictable consequence of increasing utilization of elective single embryo transfer on perinatal outcomes. Primary outcomes included twinning rates, fetal anomalies, growth, preterm birth, and mortality. Secondary outcomes included neurological and pulmonary disability, intrauterine growth restriction, and congenital cardiac anomalies and twin-twin transfusion syndrome.Data Sources: PubMed and Embase.Results: A total of 106 studies identified by systematic search met the inclusion criteria. The trend for lower numbers of embryos transferred has inadvertently led to an increase in monochorionic twinning. This is associated with worse outcomes compared to dichorionic twinning and singleton gestations for all outcomes studied.Discussion: Of great concern for monochorionic twins is the risk profile of significant morbidity and mortality. Transfer of 2 embryos should be considered to avoid higher risks inherent to the shared placental phenomena related to monochorionic twins. [ABSTRACT FROM AUTHOR]

Twin pregnancy is associated with higher rates of almost every potential complication of pregnancy. The exceptions are postterm pregnancy and macrosomia. The most serious risk is spontaneous preterm delivery, which plays a major role in the increased perinatal mortality and short-term and long-term morbidity observed in these infants. Higher rates of fetal growth restriction and congenital anomalies also contribute to adverse outcome in twin births. In addition, monochorionic twins are at risk for complications unique to these pregnancies, such as twin-twin transfusion syndrome (TTTS), twin anemia-polycythemia sequence (TAPS), twin reversed arterial perfusion sequence (TRAP) and selective fetal growth restriction which can be lethal or associated with serious morbidity. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the obstetric and neonatal outcomes of dichorionic twin (DD) pregnancies after IVF in comparison to spontaneous conception (SC). Design: Retrospective cohort study. Setting: Women Hospital – Hamad Medical Corporation, Doha, Qatar. Material and methods: All cases of DD twin pregnancies during the period from January 2002 to December 2011 were included. Demographic and clinical data, obstetric and neonatal outcomes of DD twin pregnancies after IVF and SC were compared. Main outcome measures: Maternal and neonatal outcome. Results: 145 (80%) and 175 (79.6%) DD twins after IVF and SC were included respectively. IVF was not associated with more obstetric complications than SC group. Six neonatal deaths occurred in both groups. The rate of CS was slightly but not significantly higher in IVF pregnancies (78% versus 68%). In IVF and SC there were 15 malformed fetuses in each group. Conclusions: The present study reported comparable obstetric and neonatal outcomes of DD twin pregnancies after IVF in comparison to SC provided that the same management criteria are applied to both types of twin pregnancy.

Objective: To estimate the prevalence of velamentous cord insertion (VCI) in dichorionic (DC) and monochorionic (MC) twins with and without twin-twin transfusion syndrome (TTTS), and to study the associated outcomes.Methods: We recorded the type of umbilical cord insertion in all consecutive DC and MC placentas examined in two European tertiary medical centers. The association between VCI and perinatal outcomes was estimated and compared.Results: A total of 1498 twin placentas were included in this study (DC placentas n = 550, MC placentas without TTTS n = 513 and MC placentas with TTTS n = 435). The prevalence of VCI in DC, MC without TTTS and MC with TTTS groups was 7.6%, 34.7% and 36.1%, respectively (P < 0.001). In MC twins (non-TTTS and TTTS groups), VCI was associated with severe birth weight discordance (odds ratio [OR] 4.76 95% CI 2.43, 10.47 and OR 4.52 95% CI 1.30, 28.59, respectively). In MC twins without TTTS, VCI was associated with small for gestational age (OR 1.66, 95% CI 1.12, 2.50). VCI was significantly associated with increased risk of intrauterine fetal demise in MC twins, and this effect was greater in the non-TTTS group (OR 2.71 95% CI 1.38, 5.47). These associations did not occur in DC group. Gestational age at birth was lower in the presence of VCI in the DC and MC twins without TTTS.Conclusion: Our findings confirm that the prevalence of VCI is higher in MC twins than in DC twin pregnancies. VCI is an important indicator of adverse perinatal outcome, particularly in MC twins. [ABSTRACT FROM AUTHOR]

A retrospective study conducted in an academic reproductive medicine centre evaluated the feasibility and safety of early fetal reduction in dichorionic triplets to dichorionic twin or singleton pregnancies. Thirty-three dichorionic triplets that underwent early transvaginal fetal reduction mechanically between 2002 and 2013 were included, of which 21 patients underwent fetal reduction to dichorionic twins (Group A) and 12 patients underwent fetal reduction to a singleton pregnancy (Group B). A further 84 patients with trichorionic triplets reduced to twins were included as the control group (Group C). The main outcome measures were live birth and preterm labour rates. Both early and late spontaneous abortion rates, were similar in group A compared with groups B and C. Gestational age at delivery was significantly lower in group C versus group A ( P = 0.02). The preterm labour rate in group A, which was comparable with that in group C, was greater than in group B, but not significantly. Neonatal birth weight, low birth weight rate and neonatal body height were similar among groups. Small for gestational age rates were comparable. Live birth rates were similar among the groups. Early transvaginal fetal reduction for dichorionic triplets to dichorionic twins may be feasible and safe. [ABSTRACT FROM AUTHOR]

Objective: To examine whether dichorionic twin pregnancies after assisted reproductive technology (ART) were at higher risk of adverse obstetric outcomes compared with those conceived naturally.Design: Meta-analysis.Setting: University-affiliated teaching hospital.Patient(s): Dichorionic twin pregnancies conceived with ART and naturally.Intervention(s): Studies comparing obstetric outcomes in dichorionic twin pregnancies conceived by ART and naturally were identified by searching PubMed, Google Scholar, Cochrane Libraries, and Chinese databases through July 2015 with no restrictions. Either a fixed-effects or a random-effects model was used to calculate the overall combined risk estimates. Subgroup analysis was performed to explore potential heterogeneity moderators.Main Outcome Measure(s): Maternal complications and adverse pregnancy outcomes.Result(s): Fifteen cohort studies involving 6,420 dichorionic twins after ART and 13,650 dichorionic twins conceived naturally were included. Most of maternal complications were similar in both groups, but placenta previa (relative risk [RR] = 2.99, 95% confidence interval [CI] 1.51-5.92; I(2) = 0) was significantly more common in the ART group. For neonatal outcomes, the ART group experienced higher risk of preterm birth (RR = 1.13, 95% CI 1.00-1.29; I(2) = 75%), very preterm birth (RR = 1.39, 95% CI 1.07-1.82; I(2) = 71%), low birth weight (RR = 1.11, 95% CI 1.00-1.23; I(2) = 61%), and congenital malformations (RR = 1.26, 95% CI 1.09-1.46; I(2) = 26%). In addition, the ART group had a higher proportion of elective cesarean sections (RR = 1.79, 95% CI 1.49-2.16; I(2) = 60%), but had a similar proportion for emergency cesarean sections. Relevant heterogeneity moderators have been identified by subgroup analysis. No evidence of publication bias was observed.Conclusion(s): The rates of placenta previa, elective cesarean section, preterm birth, very preterm birth, low birth weight, and congenital malformations were significantly higher in dichorionic twin pregnancies after ART. [ABSTRACT FROM AUTHOR]

Unlabelled: Our aims were to study the effect of birthweight growth discordance (≥20%) on neuro-developmental outcome of monochorionic and dichorionic twins and to compare the relative effects of foetal growth discordance and prematurity on cognitive outcome. We performed a cross-sectional multicentre prospective follow-up study from a cohort of 948 twin pregnancies. One hundred nineteen birthweight-discordant twin pairs were examined (24 monochorionic pairs) and were matched for gestational age at delivery with 111 concordant control pairs. Participants were assessed with the Bayley Scales between 24 and 42 months of age. Analysis was by paired t test for intra-twin pair differences and by multiple linear regression. Compared to the larger twin of a discordant pair, the smaller twin performed significantly worse in cognition (mean composite cognitive score difference = -1.7, 95% confidence interval (CI) = 0.3-3.1, p = 0.01) and also in language and motor skills. Prematurity prior to 33 weeks' gestation, however, had a far greater impact on cognitive outcomes (mean cognitive composite score difference = -5.8, 95% CI = 1.2-10.5, p = 0.008).Conclusion: Birthweight growth discordance of ≥20% confers an independent adverse effect on long-term neuro-development of the smaller twin. However, prior to 33 weeks' gestation, gestational age at birth adversely affects cognitive development to a greater extent than foetal growth discordance. [ABSTRACT FROM AUTHOR]