Search

Objective: Approximately, 2% of women who undergo chorionic villi sampling (CVS) will subsequently undergo amniocentesis due to placental mosaicism or sampling/laboratory issues. Our objective was to compare obstetric outcomes in women who underwent both procedures with those who had CVS alone., Study Design: Retrospective case-control study of patients with singleton pregnancies undergoing invasive testing from 2010 to 2020 was performed. All women who underwent CVS followed by amniocentesis were compared with a control group who underwent CVS alone matched (2:1) for age and year of pregnancy. Women with pregnancy loss at <16 weeks were excluded from the control group. Pregnancies terminated for genetic abnormalities were excluded. Obstetric outcomes were compared between cases and controls. Student t -test and Fisher's exact test were used for statistical comparison., Results: During the study period 2,539 women underwent CVS, and 66 (2.6%) subsequently underwent amniocentesis. The 66 cases were compared with 132 age-matched controls who underwent CVS alone. Mean maternal age was 36.8 ± 3.4 years, and 43% of women were nulliparous. Amniocentesis was performed due to sampling or laboratory issues in 33% of cases, placental mosaicism in 44%, and further diagnostic testing in 23%. There were no pregnancy losses or stillbirths in either group. Those who had two invasive procedures delivered at similar gestational ages and birthweights and did not have higher rates of adverse outcomes compared with those who underwent CVS alone., Conclusion: Patients considering CVS who are concerned about the possibility that a second invasive procedure could be required should be reassured that this does not appear to be associated with higher rates of adverse outcomes. Due to study size, we cannot exclude the possibility of small differences in uncommon outcomes, such as pregnancy loss or stillbirth., Key Points: · Amniocentesis may be recommended after CVS due to mosaicism, sampling issues, or further testing.. · Amniocentesis after CVS is not associated with pregnancy loss or other adverse outcomes compared.. · Patients who have both CVS and amniocentesis deliver at similar gestational ages and birthweights.., Competing Interests: None declared., (Thieme. All rights reserved.)

Diagnostic puncture (amniocentesis, chorionic villus sampling, and fetal blood sampling) is an essential part of prenatal diagnostics and the only established and sufficiently scientifically evaluated possibility of diagnosing genetic diseases from pregnancy-specific cells. The number of diagnostic punctures in Germany, as in other countries, has fallen significantly. This is largely due to the introduction of first-trimester screening with further detailed ultrasound examination of the fetus and the analysis of cf-DNA (cell-free DNA) from maternal blood (noninvasive prenatal test - NIPT). On the other hand, knowledge about the incidence and appearance of genetic diseases has increased. The development of modern molecular genetic techniques (microarray and exome analysis) makes a differentiated investigation of these diseases increasingly possible. The requirements for education and counseling regarding these complex correlations have thus increased. The studies performed in recent years make it clear that diagnostic puncture performed in expert centers is associated with a low risk of complications. In particular, the procedure-related miscarriage risk hardly differs from the background risk for spontaneous abortion. In 2013, the Section of Gynecology and Obstetrics of the German Society for Ultrasound in Medicine (DEGUM) published recommendations on diagnostic puncture in prenatal medicine 1. The developments described above and new findings in recent years make it necessary to revise and reformulate these recommendations. The aim of this review is to compile important and current facts regarding prenatal medical puncture (including technique, complications, genetic examinations). It is intended to provide basic, comprehensive, and up-to-date information on diagnostic puncture in prenatal medicine. It replaces the publication from 2013 1., Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht., (Thieme. All rights reserved.)

Management of severe thrombocytopenia, particularly of ITP, in pregnancy is mainly based on expert consensus and clinical experience while there are no clear indications about the minimum platelet count requested for prenatal diagnosis invasive procedures. Since the lack of specific recommendations we reported our clinical management of a patient suffering from severe thrombocytopenia, undergoing amniocentesis. Due to the anecdotic possibility of maternal and fetal bleeding in case of severe thrombocytopenia, prophylaxis with IVIG or even corticosteroids could be considered as a safer strategy to prevent post-procedural adverse outcomes., (© 2023 Walter de Gruyter GmbH, Berlin/Boston.)

Objective: To determine the safety and outcomes of trans-abdominal chorionic villus sampling technique., Study Design: Observational study., Place and Duration of Study: Departments of Obstetrics and Gynaecology, PNS Shifa Karachi, Pak-Emirates Military Hospital Rawalpindi and CMH Lahore, from 2005-2020.   Methodology: A total of 1530 consecutive chorionic villus samplings (CVS) were performed on pregnant females between 10-20 weeks of gestation using the transabdominal approach. Patients were subjected to integrated, stepwise sequential screening. Analysis of data was based on demographic features, indications for sampling, gestational age, attempts of CVS, needle aspiration time, assessment, placental location, sample yield, complications, pain estimation by visual analogue scale (VAS), CVS culture results and pregnancy outcomes., Results: The most common indication for CVS was couple having thalassemia traits and history of having a thalassemia major child previously (55.2%). Pain was the most common complication (64.1%). Procedure-related pregnancy loss (considered to be till 20 weeks of gestation) was observed in two cases (0.1%) only. The most common abnormal karyotype was found to be β-Thalassemia trait (23.6%) followed by β-Thalassemia major (22.1%) and Trisomy 21(16.8%). No abnormality was detected in 33.5% of the cases. Five hundred and eighty-nine (38.4%) interruptions of pregnancies were done on the basis of CVS results., Conclusion: CVS is a safe and useful technique for sampling in prenatal diagnosis of genetic disorders, markedly affecting the management., Key Words: Chorionic villus sampling, Pre-natal diagnosis, Karyotype.

Objectives: The purpose of the study is to investigate potential association of chorionic villus sampling ( CVS) with subsequent development of preeclampsia (PE) and eclampsia (E)., Study Design: The development of PE and E was compared between two groups as follows: 1- CVS group: women who underwent CVS ( n  = 228) and 2- Control group: maternal and gestational age matched women without invasive prenatal diagnostic procedure ( n  = 456). Main outcome measures were incidence of PE (mild, severe) and E., Results: The incidence of PE and E was not significantly different between CVS and control groups. There was no significant difference regarding mild and severe PE development between the two groups. The incidence of early- and late-onset PE was similar in CVS and control groups., Conclusions: CVS does not appear to increase the risk of PE and E. The spontaneous elevation of trophoblastic load in the maternal circulation rather than the iatrogenic elevation through CVS may contribute to the development of PE and E.

Objective: We aimed to determine foetal losses for DCDA and MCDA twins following transabdominal CVS or amniocentesis performed <22+ 0  weeks., Methods: Retrospective cohort study conducted in the UK and Belgium 01/01/00-01/06/20. Cases with unknown chorionicity, monochorionic complications or complex procedures were excluded. Uncomplicated DCDA and MCDA twins without invasive procedures were identified as controls. We reported foetal losses <24+ 0  weeks and losses of genetically and structurally normal foetuses., Results: Outcomes were compared for DCDA foetuses; 258 after CVS with 3406 controls, 406 after amniocentesis with 3390 controls plus MCDA foetuses, 98 after CVS with 1124 controls, and 160 after amniocentesis with 1122 controls. There were more losses <24+ 0  weeks with both procedures in DCDA (CVS RR 5.54 95% CI 3.38-9.08, amniocentesis RR 2.36 95% CI 1.22-4.56) and MCDA twins (CVS RR 5.14 95% CI 2.51-10.54, amniocentesis RR 7.01 95% CI 3.86-12.74). Losses of normal foetuses were comparable to controls (DCDA CVS RR 0.39 95% CI 0.05-2.83, DCDA amniocentesis RR 1.16 95% CI 0.42-3.22, MCDA CVS RR 2.3 95% CI 0.71-7.56, and MCDA amniocentesis RR 1.93 95% CI 0.59-6.38)., Conclusions: This study indicates increased foetal losses for DCDA and MCDA twins following CVS and amniocentesis with uncertain risk to normal foetuses., (© 2022 The Authors. Prenatal Diagnosis published by John Wiley & Sons Ltd.)

Purpose: The aim of this study is to evaluate the impact of the utility of maternal cell-free DNA (cfDNA) on the number of chorionic villus sampling (CVS) at a mainland Chinese maternal hospital., Methods: This was a retrospective cohort study conducted in consecutive singleton pregnancies that underwent CVS between the 11th and 14th gestational weeks at a Chinese maternal hospital during a nine-year period. The indications, complications and prenatal diagnosis results were evaluated., Results: This study consisted of 5108 CVS procedures, including 2000 performed for fetal karyotyping, and 3108 performed for fetal single-gene genotyping. During the period with the introduction of cfDNA, the proportion of the number of CVS procedures for the indication of positive serum screening declined significantly, and abnormal ultrasound was the main indication for CVS performed for fetal karyotyping. Thalassemia was always the main indication for CVS, accounting for 50.5% of all CVS cases., Conclusions: cfDNA has changed the spectrum of CVS indications. CVS is now the invasive procedure performed for patients with a fetus having a very high risk of fetal genetic defects, including fetuses having major abnormal ultrasound or having a risk of single-gene disorder inherited from their parents.

Objective: To estimate the risk of fetal loss associated with chorionic villus sampling (CVS) in twin pregnancy, using propensity score analysis., Methods: This was a multicenter cohort study of women with twin pregnancy undergoing ultrasound examination at 11-13 weeks' gestation, performed in eight fetal medicine units in which the leadership were trained at the Harris Birthright Research Centre for Fetal Medicine in London, UK, and in which the protocols for screening, invasive testing and pregnancy management are similar. The risk of death of at least one fetus was compared between pregnancies that had and those that did not have CVS, after propensity score matching (1:1 ratio). This procedure created two comparable groups by balancing the maternal and pregnancy characteristics that lead to CVS being performed, similar to how randomization operates in a randomized clinical trial., Results: The study population of 8581 twin pregnancies included 445 that had CVS. Death of one or two fetuses at any stage during pregnancy occurred in 11.5% (51/445) of pregnancies in the CVS group and in 6.3% (515/8136) in the non-CVS group (P < 0.001). The propensity score algorithm matched 258 cases that had CVS with 258 non-CVS cases; there was at least one fetal loss in 29 (11.2%) cases in the CVS group and in 35 (13.6%) cases in the matched non-CVS group (odds ratio (OR), 0.81; 95% CI, 0.48-1.35; P = 0.415). However, there was a significant interaction between the risk of fetal loss after CVS and the background risk of fetal loss; when the background risk was higher, the risk of fetal loss after CVS decreased (OR, 0.46; 95% CI, 0.23-0.90), while, in pregnancies with a lower background risk of fetal loss, the risk of fetal loss after CVS increased (OR, 2.45; 95% CI, 0.95-7.13). The effects were statistically significantly different (P-value of the interaction = 0.005). For a pregnancy in which the background risk of fetal loss was about 6% (the same as in our non-CVS population), there was no change in the risk of fetal loss after CVS, but, when the background risk was more than 6%, the posterior risk was paradoxically reduced, and when the background risk was less than 6%, the posterior risk increased exponentially; for example, if the background risk of fetal loss was 2.0%, the relative risk was 2.8 and the posterior risk was 5.6%., Conclusion: In twin pregnancy, after accounting for the risk factors that lead to both CVS and spontaneous fetal loss and confining the analysis to pregnancies at lower prior risk, CVS seems to increase the risk of fetal loss by about 3.5% above the patient's background risk. © 2021 International Society of Ultrasound in Obstetrics and Gynecology., (© 2021 International Society of Ultrasound in Obstetrics and Gynecology.)

The aim of this retrospective cohort study was to review rate of miscarriage following antenatal invasive diagnostic procedures from a unit where relatively low annual numbers of procedures are undertaken. Data were analysed for 201 chorionic villous samplings (CVSs) performed between January 2007 and June 2019 and 511 amniocenteses performed between January 2008 and June 2019, in singleton pregnancies. The miscarriage rates after CVS was 0% at 48 hours, 0.6% at 2 weeks and 2.5% up to 24 weeks of gestation. All four miscarriages following CVS had significant inherent high-risk features, therefore, it would be inappropriate to attribute these losses solely to the procedure itself. None of the women who had an amniocentesis had a miscarriage during the study period. We did not find a causal association between number of invasive procedures performed by an operator and miscarriage rate in our setting even with low annual numbers of invasive procedures.Impact Statement What is already known on this subject? Royal College of Obstetricians and Gynaecologists (RCOG) of UK recommends a minimum of at least 30 CVSs or amniocenteses procedures per year for a practitioner in order to maintain skills. A centre performing more fetal invasive procedures has lower miscarriage rates due to more experience of practitioners. What the results of this study add? This study is the first long-term audit data from a smaller fetal medicine unit with relatively low annual case load, suggesting that miscarriage risk may actually be lower than the current understanding. No additional risk of miscarriage or pregnancy loss following fetal invasive procedures even with relatively low annual numbers than that recommended by the RCOG. What the implications are of these findings for clinical practice and/or further research? The findings of this study are important in the era of non-invasive prenatal testing which will see the overall number of fetal invasive procedures decline with time. Competence in safely undertaking antenatal invasive procedure can possibly be maintained with lower annual procedure numbers. Units undertaking low number of antenatal invasive procedure must continuously audit their practice to ensure satisfactory standards and outcomes. More research is needed from smaller units to corroborate or refute the findings of this study.

Objectives: Chorionic villus sampling (CVS) allows for earlier results for aneuploidy or genomic abnormalities compared to amniocentesis. Nevertheless, the inability to provide complete results has been described as being more frequent with CVS. This study was conducted in order to identify risk factors for such failures., Study Design: A retrospective single-center study was performed from January 2014 to December 2018. Participants were divided into two groups depending on whether complete CVS results were issued ("successful CVS group") or not ("failed CVS group"). Failure affected preliminary short-term cultures, long-term cultures, or both., Results: During the study period, 214 CVS were performed, 73 (34%) of which were classified in the failed CVS group. We observed significant intergroup differences between the successful and failed CVS groups for four variables: BMI (respectively 23.9 [±5.88] and 25.9 [±6.13] kg/m 2 ), term at sampling (12.9 [±1.35] and 12.6 [±1.09] weeks gestation), trophoblastic location (posterior in 49 [40%] and 37 [66%] cases), and sampling approach (transcervical in 54 [43%] and 36 [64%] cases) ( p  < .05). In a stepwise binary logistic regression analysis, higher BMI, posterior trophoblastic location, and transcervical sampling approach were the only variables negatively influencing CVS success, with respective aOR [95% CI] of 0.947 [0.898; 0.996], 0.322 [0.160; 0.634], and 0.466 [0.238; 0.900]., Conclusions: In the presence of CVS failure risk factors, a discussion could be initiated regarding a deferred amniocentesis as a first option.

Objective: To estimate the chorionic villus sampling (CVS)-related risk of fetal loss in twin pregnancy after adjustment for chorionicity, nuchal translucency thickness (NT), intertwin discordance in crown-rump length (CRL), maternal demographic characteristics and serum pregnancy-associated plasma protein-A (PAPP-A) and free β-human chorionic gonadotropin (β-hCG)., Methods: This was a multicenter study from eight fetal medicine units in which the leadership were trained at the Harris Birthright Research Centre for Fetal Medicine in London, UK, and in which the protocols for screening, invasive testing and pregnancy management are similar. Data were obtained prospectively from women with twin pregnancy undergoing routine ultrasound examination at 11-13 weeks' gestation. Multivariable logistic regression analysis with backward stepwise elimination was used to examine whether CVS provided a significant independent contribution to the prediction of risk of fetal loss after adjusting for maternal and pregnancy characteristics, including maternal age, racial origin and weight, method of conception, smoking status, parity, chorionicity, intertwin discordance in CRL, fetal NT ≥ 95 th percentile and free β-hCG and PAPP-A multiples of the median. Similarly, within the CVS group, multivariable logistic regression analysis was used to investigate the effect of the number of intrauterine needle insertions and size of the needle on the risk of fetal loss., Results: The study population of 8581 twin pregnancies undergoing ultrasound examination at 11-13 weeks' gestation included 316 dichorionic and 129 monochorionic twins that had CVS. First, in twin pregnancies undergoing CVS, compared to those not undergoing CVS, there was a 2-fold increased risk of fetal loss at < 24 weeks' gestation and of loss at any stage in pregnancy. Second, the factors providing a significant independent contribution to the prediction of miscarriage or fetal loss in twin pregnancy were increased maternal weight, black racial origin, monochorionicity, and more so monoamnionicity, large intertwin discordance in CRL and increased fetal NT, and, in the case of fetal loss at any stage, there was also a contribution from assisted conception and low serum PAPP-A. Third, after adjustment for maternal and pregnancy characteristics, CVS did not provide a significant contribution to the risk of fetal loss. Fourth, in twin pregnancies that had CVS, there was no significant contribution to fetal loss from the number of intrauterine needle insertions or needle size., Conclusion: The 2-fold increased risk of fetal loss following CVS in twin pregnancy can, to a great extent, be explained by maternal and pregnancy characteristics rather than the invasive procedure itself. © 2021 International Society of Ultrasound in Obstetrics and Gynecology., (© 2021 International Society of Ultrasound in Obstetrics and Gynecology.)

Introduction: Amniocentesis and chorionic villus sampling remain the cornerstone of prenatal diagnosis. These procedures are associated with a risk of miscarriage estimated at approximately 0.5 %. Our team has developed a training model for performing simulation-based prenatal invasive procedures. Several simulation sessions are offered each year to obstetricians-gynecologists involved in fetal medicine in France and abroad. This simulation-based learning has already been conclusively evaluated according to levels I and II of the Kirkpatrick model. Here, we carried out a preliminary study according to level III: does participation in training in prenatal invasive procedures through simulation have an influence on professional practice?, Methods: An anonymous online survey was sent to 82 obstetricians-gynecologists who participated in the training in prenatal invasive procedures at the Antoine Béclère maternity hospital between January 1 st , 2014 and December 31, 2018. This questionnaire, entitled "Evaluation of the professional impact of training in invasive procedures through simulation", included 20 quantitative and qualitative items., Results: 48 (59 %) obstetricians-gynecologists responded to the questionnaire. 98 % of the participants considered that participation in the training had a significant impact on their professional practice. Half considered this impact to be major. 60 % of the former participants are now attached to a Multidisciplinary Center for Prenatal Diagnosis., Conclusion: Participation in training is considered by former participants to have a significant impact on their professional practice. In order to finalize the evaluation of this learning, a study of the benefits for patients and their pregnancy should be discussed., Competing Interests: Declaration of Competing Interest The authors declare no conflict of interest, (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

Introduction: The aim of this study was to obtain expert consensus on the content of a curriculum for learning chorionic villus sampling (CVS) and amniocentesis (AC) and the items of an assessment tool to evaluate CVS and AC competence., Methods: We used a 3-round iterative Delphi process. A steering committee supervised all processes. Seven international collaborators were identified to expand the breadth of the study internationally. The collaborators invited fetal medicine experts to participate as panelists. In the first round, the panelists suggested content for a CVS/AC curriculum and an assessment tool. The steering committee organized and condensed the suggested items and presented them to the panelists in round 2. In the second round, the panelists rated and commented on the suggested items. The results were processed by the steering committee and presented to the panelists in the third round, where final consensus was obtained. Consensus was defined as support by more than 80% of the panelists for an item., Results: Eighty-six experts agreed to participate in the study. The panelists represented 16 countries across 4 continents. The final list of curricular content included 12 theoretical and practical items. The final assessment tool included 11 items, systematically divided into 5 categories: pre-procedure, procedure, post-procedure, nontechnical skills, and overall performance. These items were provided with behavioral scale anchors to rate performance, and an entrustment scale was used for the final overall assessment., Conclusion: We established consensus among international fetal medicine experts on content to be included in a CVS/AC curriculum and on an assessment tool to evaluate CVS/AC skills. These results are important to help transition current training and assessment methods from a time- and volume-based approach to a competency-based approach which is a key step in improving patient safety and outcomes for the 2 most common invasive procedures in fetal medicine., (© 2021 S. Karger AG, Basel.)

Objective: To assess the rate of fetal loss following amniocentesis or chorionic villus sampling (CVS) in twin pregnancy., Methods: MEDLINE, EMBASE and Cochrane databases were searched for studies reporting procedure-related complications following amniocentesis or CVS in twin pregnancy. The primary outcome was the rate of procedure-related fetal loss. The secondary outcomes were fetal loss occurring before 24 weeks of gestation and fetal loss occurring within 4 weeks after the procedure. Head-to-head meta-analyses were used to compare directly each outcome, between women undergoing amniocentesis and those not undergoing amniocentesis and between women undergoing CVS and those not undergoing CVS, and to compute pooled risk differences (RD) between women exposed and those not exposed to each invasive procedure. Additionally, meta-analyses of proportions were used to estimate the pooled rates of each of the three outcomes in women undergoing amniocentesis or CVS and in controls., Results: Sixteen studies (3419 twin pregnancies undergoing and 2517 not undergoing an invasive procedure) were included. Head-to-head meta-analyses comparing directly twin pregnancies undergoing and those not undergoing amniocentesis showed a higher risk for overall fetal loss in those undergoing amniocentesis (odds ratio (OR), 1.46 (P = 0.04); RD, 0.013 (P = 0.04)), while there was no difference in the risk of either fetal loss before 24 weeks of gestation (OR, 1.59 (P = 0.06); RD, 0.010 (P = 0.11)) or fetal loss within 4 weeks after the procedure (OR, 1.38 (P = 0.3); RD, 0.003 (P = 0.8)). Overall, the pooled rate of fetal loss was 2.4% (95% CI, 1.4-3.6%) in twin pregnancies undergoing amniocentesis compared with 2.4% (95% CI, 0.9-4.6%) in those not undergoing amniocentesis. Head-to-head meta-analyses directly comparing twin pregnancies undergoing and those not undergoing CVS showed no significant difference in either overall fetal loss (OR, 1.61 (P = 0.5); RD, 0.003 (P = 0.8)) or fetal loss before 24 weeks of gestation (OR, 1.61 (P = 0.5); RD, 0.003 (P = 0.8)). Overall, the pooled rate of fetal loss was 2.0% (95% CI, 0.0-6.5%) in twin pregnancies undergoing CVS compared with 1.8% (95% CI, 0.3-4.2%) in those not undergoing CVS., Conclusion: The risk of fetal loss following amniocentesis and CVS in twins is lower than reported previously and the rate of fetal loss before 24 weeks of gestation, or within 4 weeks after the procedure, did not differ from the background risk in twin pregnancy not undergoing invasive prenatal testing. These data can guide prenatal counseling for twin pregnancies undergoing invasive procedures. © 2020 International Society of Ultrasound in Obstetrics and Gynecology., (© 2020 International Society of Ultrasound in Obstetrics and Gynecology.)

Objective: To estimate the risk of miscarriage associated with chorionic villus sampling (CVS)., Methods: This was a retrospective cohort study of women attending for routine ultrasound examination at 11 + 0 to 13 + 6 weeks' gestation at one of eight fetal-medicine units in Spain, Belgium and Bulgaria, between July 2007 and June 2018. Two populations were included: (1) all singleton pregnancies undergoing first-trimester assessment at Hospital Clínico Universitario Virgen de la Arrixaca in Murcia, Spain, that did not have CVS (non-CVS group); and (2) all singleton pregnancies that underwent CVS following first-trimester assessment at one of the eight participating centers (CVS group). We excluded pregnancies diagnosed with genetic anomalies or major fetal defects before or after birth, those that resulted in termination and those that underwent amniocentesis later in pregnancy. We used propensity score (PS) matching analysis to estimate the association between CVS and miscarriage. We compared the risk of miscarriage of the CVS and non-CVS groups after PS matching (1:1 ratio). This procedure creates two comparable groups balancing the maternal and pregnancy characteristics that are associated with CVS, in a similar way to that in which randomization operates in a randomized clinical trial., Results: The study population consisted of 22 250 pregnancies in the non-CVS group and 3613 in the CVS group. The incidence of miscarriage in the CVS group (2.1%; 77/3613) was significantly higher than that in the non-CVS group (0.9% (207/22 250); P < 0.0001). The PS algorithm matched 2122 CVS with 2122 non-CVS cases, of which 40 (1.9%) and 55 (2.6%) pregnancies in the CVS and non-CVS groups, respectively, resulted in a miscarriage (odds ratio (OR), 0.72 (95% CI, 0.48-1.10); P = 0.146). We found a significant interaction between the risk of miscarriage following CVS and the risk of aneuploidy, suggesting that the effect of CVS on the risk of miscarriage differs depending on background characteristics. Specifically, when the risk of aneuploidy is low, the risk of miscarriage after CVS increases (OR, 2.87 (95% CI, 1.13-7.30)) and when the aneuploidy risk is high, the risk of miscarriage after CVS is paradoxically reduced (OR, 0.47 (95% CI, 0.28-0.76)), presumably owing to prenatal diagnosis and termination of pregnancies with major aneuploidies that would otherwise have resulted in spontaneous miscarriage. For example, in a patient in whom the risk of aneuploidy is 1 in 1000 (0.1%), the risk of miscarriage after CVS will increase to 0.3% (0.2 percentage points higher)., Conclusions: The risk of miscarriage in women undergoing CVS is about 1% higher than that in women who do not have CVS, although this excess risk is not solely attributed to the invasive procedure but, to some extent, to the demographic and pregnancy characteristics of the patients. After accounting for these risk factors and confining the analysis to low-risk pregnancies, CVS seems to increase the risk of miscarriage by about three times above the patient's background risk. Although this is a substantial increase in relative terms, in pregnancies without risk factors for miscarriage, the risk of miscarriage after CVS remains low and similar to, or slightly higher than, that in the general population. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd., (Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.)

Purpose: To compare the adverse pregnancy outcomes between the pregnant women undergoing chorionic villous sampling (CVS) and those without CVS. Materials and methods: A cohort study was conducted on low risk pregnancies attending Chiang Mai University Hospital between years 2003 and 2017 and identify the database of women undergoing CVS (study group) and control group. Each case in study group was matched for 10 cases of the control by maternal age and year of procedure. Results and conclusions: Of 1384 pregnancies undergoing CVS, 776 cases met criteria and were matched with 7760 controls. The gestational age at delivery and actual birth weight were significantly different between two groups (38.02 versus 38.96 weeks, p value <.001 and 3025 versus 3092 g, p value .001). Moreover, CVS group had significantly higher preterm birth (9.4 versus 7.3%, p value .037; RR 1.287, 95% CI 1.017-1.629). However, there was no significant difference in fetal loss rate before 24 weeks (1.16 versus 1.9%, p value .14), small for gestational age (SGA); SGA (4 versus 4%, p value .948) and low birth weight (LBW); LBW (8.9 versus 8.0%, p value .41). Pregnancies undergoing CVS tend to deliver earlier and has significantly higher preterm birth. However, the incidences of fetal loss, SGA and LBW are not significantly increased.

Objectives: The purpose of this study was to estimate our center-specific CVS-related miscarriage rate., Methods: This is an observational retrospective study of women submitted to a CVS in our hospital, between January 1 st , 2007 and December 31 st , 2016. Maternal and pregnancy characteristics, procedure details, genetic results and pregnancy outcomes of all patients were collected. The FMF miscarriage risk algorithm was used to estimate our population expected risk of miscarriage. To establish the procedure-related risk of miscarriage, we compared the observed with the expected miscarriage rate., Results: We had a total number of 1523 women with a singleton pregnancy who did a CVS over the 10-year period. The mean maternal age was 34 years old; the majority of the women was Caucasian, multiparous and had a spontaneous pregnancy. The most common indication for CVS was a high-risk result in the 1 st trimester combined screening test. The karyotype was normal in 72,7% of cases, 11,1% were T21 and 7,2% were T13 or T18. In the study group, 33 women were diagnosed with a fetal demise, 435 had a TOP and there were 4 intrauterine deaths and 34 miscarriages. The rate of miscarriage in our population was 3,2% and the expected patient specific risk for miscarriage was 3,0%. There was no statistical significance between the two miscarriage rates p = 0,705., Conclusion: In our study the risk of miscarriage in the CVS group was not significantly different from that the expected patient specific risk (3.2 % vs 3%, p = 0.7). The procedure-related risk of miscarriage was 0,2%, similar to the rates describe in the literature. An accurate risk of pregnancy loss should be used when counseling women for CVS to allow an informed decision., Competing Interests: Declaration of Competing Interest There is no conflict of interest in the work presented., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

Objective: To evaluate the effects of chorionic villus sampling (CVS) on placental volume (PV), perfusion, and vasculature in the first trimester of pregnancy. Method: Uterine artery pulsatility index (PI), PV, vascularization index (VI), flow index (FI), and Vascularization Flow Index (VFI) were serially measured in 38 pregnant women who underwent CVS. Thirty-eight women who did not undergo invasive prenatal diagnosis were recruited as controls. Results: CVS was associated with a mild reduction of PI, a reduction of placental VI, FI, and VFI and with an increase in PV detected one week after the procedure. The outcome of pregnancy was similar between women of the two groups. Conclusion: Our findings showed that CVS is associated with mild placental vascular and morphological changes. However, these changes do not seem to be associated with adverse outcome.

Objective: To evaluate the risk of inducing RhD immunisation in pregnancies of RhD-negative mothers with an RhD-positive fetus undergoing chorionic villus samplings (CVS) or amniocenteses (AC)., Design, Setting and Population: Registry-based study in a Danish cohort which has not been given rhesus prophylaxis., Methods: Data were retrieved from the Department of Clinical Immunology at Rigshospitalet. All RhD-negative women carrying an RhD-positive fetus with screen test results from weeks 8-12 and weeks 25-29 were linked to data from the Danish Fetal Medicine Database. Data were divided into cases where no invasive prenatal diagnostic procedure was performed, cases that had AC performed, and cases that had CVS performed., Main Outcome Measures: A comparison of the proportion of women who developed RhD immunisation between the two screen tests., Results: The cohort consisted of 10 085 women: 9353 had no invasive procedures performed, 189 had AC and 543 had CVS performed. No women were immunised spontaneously or due to the procedure between the first and second screen test in the group with no procedure performed, or in the AC group. One woman was immunised in the CVS group. When comparing the proportion of women who was immunised in the CVS group with the no invasive test group a non-significant difference was found (P = 0.055)., Conclusion: The RhD immunisation rate before gestational weeks 25-29 in RhD-negative women carrying an RhD-positive fetus is very low, even in women undergoing prenatal invasive testing without rhesus prophylaxis., Tweetable Abstract: The RhD immunisation rate during pregnancy is very low even in women undergoing prenatal invasive testing., (© 2019 Royal College of Obstetricians and Gynaecologists.)

Background The aim of this study was to compare transabdominal and transcervical chorionic villus sampling (CVS) as well as amniocentesis (AC) with respect to their rates of premature delivery and fetal growth restriction. Methods We retrospectively evaluated the mentioned procedures of invasive prenatal testing performed in a single center between 2001 and 2016. Seven hundred and ninety-nine cases of AC and 719 cases of CVS were included, of which 400 were performed transvaginally. Only singleton pregnancies with a normal karyotype and delivery after 24 + 0 weeks of gestation were included. Fetal growth restriction was defined as birth weight below the 10th percentile. Premature delivery was defined as delivery before 37 + 0 weeks of gestation. Data were compared to a control group without an invasive procedure. Results The frequency of premature delivery was 8.5% after transabdominal CVS, 6.3% after transcervical CVS and 10.5% after AC as compared to 10.8% in the control group. The frequency of fetal growth restriction was 8.2% after transabdominal CVS 6.8% after transcervical CVS and 8.4% after AC as compared to 9.7% in the control group. Conclusion Our study supports that the three different methods of invasive prenatal testing do not lead to a higher risk of either premature delivery or fetal growth restriction when compared to controls. We found no difference in risk profile among the three techniques.

Objectives: To estimate the procedure-related risks of miscarriage following chorionic villus sampling (CVS) and amniocentesis in a large unselected screened population, and to determine whether these risks are consistent with those reported in systematic reviews and meta-analyses., Methods: This was a retrospective cohort study carried out on data obtained from a large fetal medicine unit in the UK between January 2009 and May 2018. We included all women with singleton pregnancy who booked for pregnancy care at our unit before 20 weeks' gestation, after excluding those with multiple pregnancy, major fetal defect, pregnancy termination and loss to follow-up. We estimated the risk of miscarriage in women who underwent a CVS or amniocentesis as well as in those who did not have an invasive procedure. The procedure-related risk of miscarriage was estimated as risk difference (95% CI) between the two groups. Univariate and multivariate regression analyses were used to derive odds ratios (95% CI) and determine which maternal and pregnancy characteristics provided a significant contribution in the prediction of miscarriage and whether CVS or amniocentesis provided a significant independent contribution., Results: During the study period, 45 120 singleton pregnancies were booked for pregnancy care at our hospital, of which 1546 had an invasive procedure. We excluded 1429 (3.2%) pregnancies due to fetal defects, termination of pregnancy or missing outcomes. Of the 43 691 pregnancies included in the study population, 861 underwent CVS and 375 amniocentesis. In pregnancies that underwent CVS, the risk of miscarriage was 1.5% (13/861), compared with 1.2% (476/39 152) in pregnancies that had first-trimester combined screening and did not have an invasive procedure (P = 0.437). In pregnancies that underwent an amniocentesis, the risk of miscarriage was 0.8% (3/375), compared with 1.2% (491/42 463) in those that did not undergo an invasive procedure (P = 0.520). Univariate and multivariate regression analysis demonstrated that there was no significant contribution in the prediction of the risk of miscarriage from CVS (P = 0.399 and P = 0.592, respectively) or amniocentesis (P = 0.543 and P = 0.550, respectively). The risk of procedure-related loss attributed to CVS was 0.29% (95% CI, -0.53 to 1.12%) and that following amniocentesis was -0.36% (95% CI, -1.26 to 0.55%), which was not significantly different from the risk in women who did not have any procedure., Conclusions: The procedure-related risks of miscarriage following CVS and amniocentesis in our study are considerably lower than those currently quoted and are consistent with the estimates of such risks reported by systematic reviews and meta-analyses. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd., (Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.)

Objective: To estimate the procedure-related risk of miscarriage after amniocentesis and chorionic villus sampling (CVS) based on a systematic review of the literature and an updated meta-analysis., Methods: A search of MEDLINE, EMBASE and The Cochrane Library was carried out to identify studies reporting complications following CVS or amniocentesis. Eligible for inclusion were large controlled studies reporting data for pregnancy loss prior to 24 weeks' gestation. Study authors were contacted when required to identify additional necessary data. Data for cases that had an invasive procedure and controls were inputted into contingency tables and the risk of miscarriage was estimated for each study. Summary statistics based on a random-effects model were calculated after taking into account the weighting for each study included in the systematic review. Procedure-related risk of miscarriage was estimated as a weighted risk difference from the summary statistics for cases and controls. Subgroup analyses were performed according to the similarity in risk levels for chromosomal abnormality between the invasive-testing and control groups. Heterogeneity was assessed using the I 2 statistic. Egger's bias was estimated to assess reporting bias in published studies., Results: The electronic search yielded 2943 potential citations, from which 12 controlled studies for amniocentesis and seven for CVS were selected for inclusion in the systematic review. A total of 580 miscarriages occurred following 63 723 amniocentesis procedures, resulting in a weighted risk of pregnancy loss of 0.91% (95% CI, 0.73-1.09%). In the control group, there were 1726 miscarriages in 330 469 pregnancies with a loss rate of 0.58% (95% CI, 0.47-0.70%). The weighted procedure-related risk of miscarriage following amniocentesis was 0.30% (95% CI, 0.11-0.49%; I 2  = 70.1%). A total of 163 miscarriages occurred following 13 011 CVS procedures, resulting in a risk of pregnancy loss of 1.39% (95% CI, 0.76-2.02%). In the control group, there were 1946 miscarriages in 232 680 pregnancies with a loss rate of 1.23% (95% CI, 0.86-1.59%). The weighted procedure-related risk of miscarriage following CVS was 0.20% (95% CI, -0.13 to 0.52%; I 2  = 52.7%). However, when studies including only women with similar risk profiles for chromosomal abnormality in the intervention and control groups were considered, the procedure-related risk for amniocentesis was 0.12% (95% CI, -0.05 to 0.30%; I 2  = 44.1%) and for CVS it was -0.11% (95% CI, -0.29 to 0.08%; I 2  = 0%)., Conclusions: The procedure-related risks of miscarriage following amniocentesis and CVS are lower than currently quoted to women. The risk appears to be negligible when these interventions were compared to control groups of the same risk profile. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd., (Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.)

Objective: To assess the risk of preeclampsia in women who underwent chorionic villus sampling (CVS). Study design: This is a retrospective, single-center, cohort study. All consecutive singleton gestations who underwent chorionic villus sampling from January 2014 to January 2016 were included in the study. The primary outcome was the incidence of preeclampsia. Subgroup analysis in women with beta thalassemic trait was performed. Logistic regression, presented as adjusted odds ratio (aOR) with the 95% of confidence interval (CI), was performed. Results: Five hundred forty-seven women who underwent CVS, and 1532 women who did not were analyzed. Women who underwent CVS had a significantly lower risk of preeclampsia (4.4 versus 8.0%; aOR 0.53, 95%CI 0.34-0.83), and late-onset preeclampsia (3.3 versus 6.1%; aOR 0.52, 95%CI 0.31-0.87). No statistically significant differences were found in preeclampsia with severe features, early-onset preeclampsia, and preterm birth (PTB). Women who underwent CVS due to thalassemic trait had a lower incidence of preeclampsia compare to those women who did not undergo CVS (3.3 versus 8.0%; aOR 0.39, 95%CI 0.14-0.87), while no differences were found comparing women who underwent CVS due to thalassemic trait with women who underwent CVS due to other reasons. Conclusions: Women who underwent first trimester CVS had a lower risk of preeclampsia compared to those who did not.

Aim: Prenatal diagnostic testing by chorionic villus sampling (CVS) is sometimes recommended for women with twin pregnancies. However, few studies have compared the outcomes between twins with CVS and control twins without intervention. This study aimed to compare the obstetrical outcomes of CVS in twin pregnancies and those in non-intervention twin pregnancies., Methods: First-trimester transabdominal CVS was performed on dichorionic-diamniotic twins (n = 54; Group 1) between December 2006 and January 2017 at the Department of Obstetrics and Gynecology at our hospital, and the data were retrospectively analyzed. CVS risks were evaluated by comparing obstetrical outcomes with those of a control population of 155 dichorionic-diamniotic twins without intervention (Group 2)., Results: The difference in the overall fetal loss rate (Group 1, 7.4% vs Group 2, 3.9%; P = 0.287) between the two groups was not statistically significant. The miscarriage rate, defined as delivery at <24 gestational weeks, and early preterm delivery, defined as delivery at <34 gestational weeks, were not significant between the groups (miscarriage: Group 1, 5.6% vs Group 2, 3.2%; P = 0.428; early preterm delivery: Group 1, 11.1% vs Group 2, 9.0%; P = 0.788). The mean gestational age at delivery, birth weights and neonatal intensive care unit admission rate were not statistically significant between the groups. Thus, the overall fetal loss rate and obstetrical outcomes of Group 1 were comparable with those of Group 2., Conclusion: In conclusion, the overall obstetrical outcomes were not significantly different between twins with CVS and control twins with the advantage of enabling early decision-making about selective feticide in twins with CVS., (© 2019 Japan Society of Obstetrics and Gynecology.)

Purpose: To assess the complication rates following chorionic villus sampling (CVS) and midtrimester amniocentesis in Taiwan., Methods: This is a national registry-based cohort study from Taiwan. We included all women with singleton pregnancies who received either CVS (n = 1409) or midtrimester amniocentesis (n = 250,566) during 2006-2012. We assessed preterm premature rupture of membranes (PPROM), intrauterine fetal demise (IUFD), infection and spontaneous abortion (SA) that occurred within fourteen days after the procedures. We also assessed the risks of preterm delivery and miscarriage before 24 gestational weeks after amniocentesis. These complications were collected from the Genetic Disease Database of the Ministry of Health and Welfare, Taiwan National Birth Certificate Registry, and the Taiwan National Health Insurance Database. Pearson χ 2 tests were used to compare the distributions between groups., Results: For patients who underwent midtrimester amniocentesis, the rates of PPROM, IUFD, infection and SA within fourteen days were 0.24%, 0.11%, 0.05%, and 0.05%, respectively. Women with a normal fetal karyotype had a preterm birth rate (<37 gestational weeks) of 9.38%. The miscarriage rate (<24 gestational weeks) was 0.68%, which was 0.22% higher than those who did not receive the invasive procedures (p < 0.0001). After CVS, the IUFD rate was 1.68%, and the SA rate within fourteen days was 0.77%., Conclusion: The use of our large cohort demonstrated that the procedure-related complication rates were comparable to recent review or meta-analysis. This dataset might facilitate counselling in women who consider invasive genetic diagnostic procedures., (Copyright © 2019. Published by Elsevier B.V.)

Background: Under certain situations, women with twin pregnancies may be counseled to undergo invasive prenatal diagnostic testing. Chorionic villus sampling and amniocentesis are the two generally performed invasive prenatal diagnostic tests. Studies comparing procedure-related fetal loss between first-trimester chorionic villus sampling and second-trimester amniocentesis in twin pregnancies are limited. This study aimed to evaluate the procedure-related fetal loss and the obstetrical outcomes of these two procedures, chorionic villus sampling and amniocentesis in twin pregnancies., Methods: The data from dichorionic-diamniotic twin pregnancies on which first-trimester chorionic villus sampling (n = 54) or second-trimester amniocentesis (n = 170) was performed between December 2006 and January 2017 in a single center were retrospectively analyzed. The procedure-related fetal loss was classified as loss of one or all fetuses within 4 weeks of procedure, and overall fetal loss was classified as loss of one or all fetuses during the gestation. The groups were compared with respect to the procedure-related and obstetrical outcomes., Results: The difference in proportion of procedure-related fetal loss rate (1.9% for chorionic villus sampling vs. 1.8% for amniocentesis; P = 1.000) and the overall fetal loss rate (7.4% for chorionic villus sampling vs. 4.7% for amniocentesis; P = 0.489) between the two groups was not significant. The mean gestational ages at delivery were not statistically significant., Conclusion: Both the overall fetal loss rate and the procedure-related fetal loss rate of chorionic villus sampling and amniocentesis in dichorionic twin pregnancies had no statistical significance. Both procedures can be safely used individually., Competing Interests: The authors have no potential conflicts of interest to disclose., (© 2019 The Korean Academy of Medical Sciences.)

Introduction: Transabdominal chorionic villus sampling (CVS) is an invasive procedure for prenatal diagnosis reported to be associated with anxiety and pain. In this context, the need for analgesia during CVS has been considered useful. Even though several authors have been interested in pain management during amniocentesis, no study has been published on pain reduction during CVS. Our objective was to evaluate pain and anxiety management during transabdominal CVS using nitrous oxide (N 2 O) and local anesthesia., Material and Methods: In a randomized controlled noninferiority trial, self-administered nitrous oxide (N 2 O) inhalation (equimolar premix of oxygen and nitrous oxide) was compared with local anesthesia (1% lidocaine) before CVS. Primary outcome was pain and secondary outcome was anxiety, both measured on a visual analog scale 30-60 minutes before, immediately after (5-10 minutes) and 30-60 minutes after CVS. With a statistical power of 90%, type I error of 5% and two-sided test and potential exclusions, a sample size of 96 patients per group was enrolled and randomized. No patient was enrolled before the trial registration date., Results: From 13 March 2013 through 10 February 2015, 192 patients (96 per group) were screened and randomized. Most characteristics were similar across groups. Pain in the N 2 O group was 2.65 ± 0.22 vs 3.32 ± 0.26 in local anesthesia group [mean ± standard error of mean  (SEM)]. Mean anxiety in the N 2 O group was 3.17 ± 0.27 vs 5.19 ± 0.30 in the local anesthesia group., Conclusion: N 2 O was as efficient and even superior to local anesthesia for both pain and anxiety reduction during CVS, as the 95% confidence intervals were both below the prespecified noninferiority margin of 0.8 and below zero., (© 2018 Nordic Federation of Societies of Obstetrics and Gynecology.)

Objective: To compare the obstetric outcome and incidence of procedure-related adverse events after embryo reduction (ER) vs fetal reduction (FR), in multifetal pregnancies undergoing reduction to twins or singletons., Methods: We analyzed retrospectively data from multifetal pregnancies that underwent transvaginal ER (n = 181) at a mean gestational age of 7.6 weeks or transabdominal FR (n = 115) at a mean gestational age of 12.9 weeks between December 2006 and January 2017. FR was performed after a detailed fetal anomaly scan. The two groups were compared with respect to obstetric outcomes, such as incidence of miscarriage, early or late preterm delivery, maternal complications and fetal loss, and procedure-related adverse events, including incidence of subchorionic hematoma and procedure-related fetal loss., Results: Compared with pregnancies that underwent ER, the incidence of procedure-related fetal loss was lower in the FR group (7.2% vs 0.9%; P = 0.039; odds ratio (OR), 0.12; 95% CI, 0.02-0.89). Mean gestational age at delivery for twins was 34.2 weeks in the ER group and 35.7 weeks in the FR group (P = 0.014). Compared with the ER group, the FR group had lower miscarriage (8.8% vs 2.6%; P = 0.045; OR, 0.28; 95% CI, 0.08-0.97) and overall fetal loss (13.3% vs 5.2%; P = 0.031; OR, 0.36; 95% CI, 0.14-0.91) rates., Conclusions: The FR procedure is, overall, a better and safer approach to reducing morbidity and mortality in multifetal pregnancies. Spontaneous demise of one fetus may occur after ER, and FR has the advantage that chorionic villus sampling and ultrasound screening for increased nuchal translucency and anatomical defects can be conducted before the procedure. The ER approach is still reasonable when a patient's religious or other ethical concerns are of primary importance. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd., (Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.)

Importance: Cell-free DNA (cfDNA) tests are increasingly being offered to women in the first trimester of pregnancies at a high risk of trisomy 21 to decrease the number of required invasive fetal karyotyping procedures and their associated miscarriages. The effect of this strategy has not been evaluated., Objective: To compare the rates of miscarriage following invasive procedures only in the case of positive cfDNA test results vs immediate invasive testing procedures (amniocentesis or chorionic villus sampling) in women with pregnancies at high risk of trisomy 21 as identified by first-trimester combined screening., Design, Setting, and Participants: Randomized clinical trial conducted from April 8, 2014, to April 7, 2016, in 57 centers in France among 2111 women with pregnancies with a risk of trisomy 21 between 1 in 5 and 1 in 250 following combined first-trimester screening., Interventions: Patients were randomized to receive either cfDNA testing followed by invasive testing procedures only when cfDNA tests results were positive (n = 1034) or to receive immediate invasive testing procedures (n = 1017). The cfDNA testing was performed using an in-house validated method based on next-generation sequencing., Main Outcomes and Measures: The primary outcome was number of miscarriages before 24 weeks' gestation. Secondary outcomes included cfDNA testing detection rate for trisomy 21. The primary outcome underwent 1-sided testing; secondary outcomes underwent 2-sided testing., Results: Among 2051 women who were randomized and analyzed (mean age, 36.3 [SD, 5.0] years), 1997 (97.4%) completed the trial. The miscarriage rate was not significantly different between groups at 8 (0.8%) vs 8 (0.8%), for a risk difference of -0.03% (1-sided 95% CI, -0.68% to ∞; P = .47). The cfDNA detection rate for trisomy 21 was 100% (95% CI, 87.2%-100%)., Conclusions and Relevance: Among women with pregnancies at high risk of trisomy 21, offering cfDNA screening, followed by invasive testing if cfDNA test results were positive, compared with invasive testing procedures alone, did not result in a significant reduction in miscarriage before 24 weeks. The study may have been underpowered to detect clinically important differences in miscarriage rates., Trial Registration: ClinicalTrials.gov Identifier: NCT02127515.

Introduction: The aim of this paper was to estimate the risk of miscarriage after amniocentesis or chorionic villus sampling (CVS) based on a systematic review of the literature., Evidence Acquisition: A search of Medline, Embase, and The Cochrane Library (2000-2017) was carried out to identify studies reporting complications following CVS or amniocentesis. The inclusion criteria for the systematic review were studies reporting results from large controlled studies (N.≥1000 invasive procedures) and those reporting data for pregnancy loss prior to 24 weeks' gestation. Data for cases that had invasive procedure and controls were inputted in contingency tables and risk of miscarriage was estimated for each study. Summary statistics were calculated after taking into account the weighting for each study included in the systematic review. Procedure-related risk of miscarriage was estimated as a weighted risk difference from the summary statistics for cases and controls., Evidence Snthesis: The electronic search from the databases yielded 2465 potential citations of which 2431 were excluded, leaving 34 studies for full-text review. The final review included 10 studies for amniocentesis and 6 studies for CVS, which were used to estimate risk of miscarriage in pregnancies that had an invasive procedure and the control pregnancies that did not. The procedure-related risk of miscarriage following amniocentesis was 0.35% (95% confidence interval [CI]: 0.07 to 0.63) and that following CVS was 0.35% (95% CI: -0.31 to 1.00)., Conclusions: The procedure-related risks of miscarriage following amniocentesis and CVS are lower than currently quoted to women.

Background: During pregnancy, fetal cells suitable for genetic testing can be obtained from amniotic fluid by amniocentesis (AC), placental tissue by chorionic villus sampling (CVS), or fetal blood. A major disadvantage of second trimester amniocentesis is that the results are available relatively late in pregnancy (after 16 weeks' gestation). Earlier alternatives are chorionic villus sampling (CVS) and early amniocentesis, which can be performed in the first trimester of pregnancy., Objectives: The objective of this review was to compare the safety and accuracy of all types of AC (i.e. early and late) and CVS (e.g. transabdominal, transcervical) for prenatal diagnosis., Search Methods: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (3 March 2017), ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP; 3 March 2017), and reference lists of retrieved studies., Selection Criteria: All randomised trials comparing AC and CVS by either transabdominal or transcervical route., Data Collection and Analysis: Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. The quality of the evidence was assessed using the GRADE approach., Main Results: We included a total of 16 randomised studies, with a total of 33,555 women, 14 of which were deemed to be at low risk of bias. The number of women included in the trials ranged from 223 to 4606.Studies were categorized into six comparisons: 1. second trimester AC versus control; 2. early versus second trimester AC; 3. CVS versus second trimester AC; 4. CVS methods; 5. Early AC versus CVS; and 6. AC with or without ultrasound.One study compared second trimester AC with no AC (control) in a low risk population (women = 4606). Background pregnancy loss was around 2%. Second trimester AC compared to no testing increased total pregnancy loss by another 1%. The confidence intervals (CI) around this excess risk were relatively large (3.2% versus 2.3 %, average risk ratio (RR) 1.41, 95% CI 0.99 to 2.00; moderate-quality evidence). In the same study, spontaneous miscarriages were also higher (2.1% versus 1.3%; average RR 1.60, 95% CI 1.02 to 2.52; high-quality evidence). The number of congenital anomalies was similar in both groups (2.0% versus 2.2%, average RR 0.93, 95% CI 0.62 to 1.39; moderate-quality evidence).One study (women = 4334) found that early amniocentesis was not a safe early alternative compared to second trimester amniocentesis because of increased total pregnancy losses (7.6% versus 5.9%; average RR 1.29, 95% CI 1.03 to 1.61; high-quality evidence), spontaneous miscarriages (3.6% versus 2.5%, average RR 1.41, 95% CI 1.00 to 1.98; moderate-quality evidence), and a higher incidence of congential anomalies, including talipes (4.7% versus 2.7%; average RR 1.73, 95% CI 1.26 to 2.38; high-quality evidence).When pregnancy loss after CVS was compared with second trimester AC, there was a clinically significant heterogeneity in the size and direction of the effect depending on the technique used (transabdominal or transcervical), therefore, the results were not pooled. Only one study compared transabdominal CVS with second trimester AC (women = 2234). They found no clear difference between the two procedures in the total pregnancy loss (6.3% versus 7%; average RR 0.90, 95% CI 0.66 to 1.23, low-quality evidence), spontaneous miscarriages (3.0% versus 3.9%; average RR 0.77, 95% CI 0.49 to 1.21; low-quality evidence), and perinatal deaths (0.7% versus 0.6%; average RR 1.18, 95% CI 0.40 to 3.51; low-quality evidence). Transcervical CVS may carry a higher risk of pregnancy loss (14.5% versus 11.5%; average RR 1.40, 95% CI 1.09 to 1.81), but the results were quite heterogeneous.Five studies compared transabdominal and transcervical CVS (women = 7978). There were no clear differences between the two methods in pregnancy losses (average RR 1.16, 95% CI 0.81 to 1.65; very low-quality evidence), spontaneous miscarriages (average RR 1.68, 95% CI 0.79 to 3.58; very low-quality evidence), or anomalies (average RR 0.68, 95% CI 0.41 to 1.12; low-quality evidence). We downgraded the quality of the evidence to low due to heterogeneity between studies. Transcervical CVS may be more technically demanding than transabdominal CVS, with more failures to obtain sample (2.0% versus 1.1%; average RR 1.79, 95% CI 1.13 to 2.82, moderate-quality evidence).Overall, we found low-quality evidence for outcomes when early amniocentesis was compared to transabdominal CVS. Spontaneous miscarriage was the only outcome supported by moderate-quality evidence, resulting in more miscarriages after early AC compared with transabdominal CVS (2.3% versus 1.3%; average RR 1.73, 95% CI 1.15 to 2.60). There were no clear differences in pregnancy losses (average RR 1.15, 95% CI 0.86 to 1.54; low-quality evidence), or anomalies (average RR 1.14, 95% CI 0.57 to 2.30; very low-quality evidence).We found one study that examined AC with or without ultrasound, which evaluated a type of ultrasound-assisted procedure that is now considered obsolete., Authors' Conclusions: Second trimester amniocentesis increased the risk of pregnancy loss, but it was not possible to quantify this increase precisely from only one study, carried out more than 30 years ago.Early amniocentesis was not as safe as second trimester amniocentesis, illustrated by increased pregnancy loss and congenital anomalies (talipes). Transcervical chorionic villus sampling compared with second trimester amniocentesis may be associated with a higher risk of pregnancy loss, but results were quite heterogeneous.Diagnostic accuracy of different methods could not be assessed adequately because of incomplete karyotype data in most studies.

Objectives: To assess in pregnant women with HIV the rates of amniocentesis and chorionic villus sampling (CVS), and the outcomes associated with such procedures., Design: Observational study. Data from the Italian National Program on Surveillance on Antiretroviral Treatment in Pregnancy were used., Setting: University and hospital clinics., Population: Pregnant women with HIV., Methods: Temporal trends were analysed by analysis of variance and by the Chi-square test for trend. Quantitative variables were compared by Student's t-test and categorical data by the Chi-square test, with odds ratios and 95% confidence intervals calculated., Main Outcome Measures: Rate of invasive testing, intrauterine death, HIV transmission., Results: Between 2001 and 2015, among 2065 pregnancies in women with HIV, 113 (5.5%) had invasive tests performed. The procedures were conducted under antiretroviral treatment in 99 cases (87.6%), with a significant increase over time in the proportion of tests performed under highly active antiretroviral therapy (HAART) (100% in 2011-2015). Three intrauterine deaths were observed (2.6%), and 14 pregnancies were terminated because of fetal anomalies. Among 96 live newborns, eight had no information available on HIV status. Among the remaining 88 cases with either amniocentesis (n = 75), CVS (n = 12), or both (n = 1), two HIV transmissions occurred (2.3%). No HIV transmission occurred among the women who were on HAART at the time of invasive testing, and none after 2005., Conclusions: The findings reinforce the assumption that invasive prenatal testing does not increase the risk of HIV vertical transmission among pregnant women under suppressive antiretroviral treatment., Tweetable Abstract: No HIV transmission occurred among women who underwent amniocentesis or CVS under effective anti-HIV regimens., (© 2016 Royal College of Obstetricians and Gynaecologists.)

Objectives: To identify maternal-, operator- and procedure-related variables that affect procedure-related pregnancy loss after transcervical (TC) and transabdominal (TA) chorionic villus sampling (CVS) and amniocentesis and to estimate the rates of spontaneous and procedure-related loss in comparable subgroups of women., Methods: This was a retrospective cohort study conducted at the University Medical Center Groningen and the Academic Medical Center, The Netherlands. Databases of both centers were searched to identify singleton pregnancies that had undergone a combined test and/or anomaly scan at around 20 weeks' gestation, or an invasive procedure (CVS and/or amniocentesis) between January 2001 and December 2011. Maternal characteristics, obstetric history, technical aspects of the invasive procedure, ultrasound examinations and fetal and neonatal outcomes were available for 29 201 cases. Women were categorized, according to the type of examination they had received, into the following five groups: first-trimester combined test (and 20-week anomaly scan); 20-week anomaly scan only; CVS; amniocentesis; amniocentesis after unsuccessful CVS. Rates of fetal loss were compared between groups., Results: Variables significantly associated with a higher rate of fetal loss were, for CVS, repeat attempts during the procedure, use of TC cannula instead of biopsy forceps, gestational age at procedure ≥ 13 weeks and a pregnancy after assisted reproductive techniques, and, for amniocentesis, if indication was fetal anomaly or family history of anomalies and repeat attempts during the procedure. In women aged ≥ 36 years who did not undergo an invasive procedure, spontaneous fetal loss rate (FLR) after first-trimester combined test was 1.40%, whereas after CVS, FLR was 2.76% and 2.43% for a TC and TA approach, respectively. The additional risk of fetal loss with TC-CVS was therefore 1.36% (1 : 74), which varied according to the instrument used (0.27% for forceps and 3.12% for cannula), and with TA-CVS was 1.03% (1 : 97). In women aged ≥ 36 years who underwent a 20-week anomaly scan only, spontaneous FLR was 0.63%. In women who underwent amniocentesis solely because of advanced maternal age, FLR was 1.11%. The additional risk of fetal loss with amniocentesis was 0.48% (1 : 208)., Conclusion: The total rate of procedure-related fetal loss after TA- and TC-CVS and amniocentesis appears lower than the risks on which women are currently counseled. There was a trend for a decrease in risk when the level of experience of the operator increased. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd., (Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.)

Objective: To determine the impact of the chorion villus sampling (CVS) technique on adverse perinatal outcomes., Methods: In this case-control study, 412 women who underwent CVS at 11-14 weeks of gestation and 231 women who did not undergo any invasive procedure were retrospectively evaluated. The women in the CVS group were further divided into two groups according to the use of single-needle technique (n=148) vs. double-needle technique (n=264). The adverse outcomes were compared between controls and the two CVS groups, and regression analysis was used to determine the significance of independent contribution., Results: The rate of preeclampsia for the control group was 2.2%, for the double-needle group was 3% and for the single-needle group was 8.1%. CVS with single-needle technique was found to be an independent and statistically significant risk factor for preeclampsia [odds ratio (OR)=2.1, 95% confidence interval (CI); 1.4-2.7, P=0.008]., Conclusion: The risk of preeclampsia after CVS appears to be increased with single-needle technique compared with double-needle technique.

Objective: The aim of this study was to compare transabdominal chorionic villus sampling, transcervical chorionic villus sampling and amniocentesis with respect to their total fetal loss rates., Methods: We retrospectively evaluated procedures of invasive prenatal testing performed during a 14-year period (2001-2014) including 936 amniocentesis procedures and 1051 chorionic villus samplings, of which 405 cases were executed transabdominally and 646 transcervically. Only singleton pregnancies before 24 weeks and 0 days of gestation where the pregnancy outcome was known were included. Fetal loss was defined as an abortion occurring either before 24 weeks and 0 days of gestation or <2 weeks after the procedure., Results: The total fetal loss rates were determined to be 1.73% for transabdominal chorionic villus sampling, 2.01% for transcervical chorionic villus sampling and 1.18% for amniocentesis. No statistically noticeable differences between the total fetal loss rates of all three procedures were found (P=0.399)., Conclusion: Our study has shown that chorionic villus sampling (either transabdominal or transcervical) and amniocentesis are equal methods for invasive prenatal testing with respect to their abortion risk.

Objective: The aim was to determine the institutional procedure-related fetal loss rate after chorionic villus sampling (CVS) and the factors which may identify pregnancies at increased risk of having a procedure-related loss., Materials and Methods: Pregnancy outcomes were retrieved of all women having a singleton pregnancy and undergoing a CVS procedure between 2004 and 2013 at a university hospital in Hong Kong. The incidence of procedure-related fetal loss due to unintended miscarriages adjusted for the background loss incidence of miscarriages was determined. Multivariate regression was performed to examine the factors contributing to an unintended fetal loss and miscarriage., Results: CVS was performed on 1,906 fetuses. The procedure-related fetal loss rate was 0.17% (95% CI -0.2 to 0.7). After multivariate analysis, a decreased plasma protein-A (PAPP-A) multiple of the median (OR 0.27; 95% CI 0.08-0.98, p = 0.046) was significantly associated with miscarriage in women who did not undergo a CVS. Patient-specific prediction of spontaneous abortion in women who did not undergo CVS was not statistically significant (AUC 0.56; 95% CI 0.49-0.6, p = 0.14)., Conclusions: The CVS-related fetal loss rate adjusted for background loss was 0.17%. Pregnancies with reduced PAPP-A carry an increased risk of miscarriage irrespective of whether they had undergone an invasive procedure., (© 2016 S. Karger AG, Basel.)

Objectives: To quantify the learning curve for a training program for Maternal Fetal Medicine (MFM) fellows in obtaining successful transvaginal chorionic villus sampling (CVS) results in women with early pregnancy failure (EPF)., Methods: Retrospective observational cohort study of transvaginal CVS and subsequent manual vacuum aspiration (MVA) performed by MFM fellows. CVS samples were sent for karyotype, and products of conception (POC) were sent if CVS sample did not yield a result. Success was defined as karyotype result on CVS specimen., Results: A total of 130 women with EPF up to 9 weeks of gestation underwent transvaginal CVS and MVA from December 2011 to April 2015. CVS samples were successful in 53 (40.8%) cases, POC were analyzed for karyotype in 68 (52.3%) cases, and maternal decidua was obtained in 9 (6.9%) cases. Nine MFM fellows performed the CVS and MVA procedures. The mean number of procedures per fellow was 14 (5-24). The average success rate of transvaginal CVS sample was 33.3% after the first procedure and 50% at the 14th procedure. One procedure was performed per patient., Conclusions: Success increased over time from 33.3% to 50.0%. Given the gestational age and failed pregnancy status, this is a reasonable success rate for CVS at time of EPF. © 2016 John Wiley & Sons, Ltd., (© 2016 John Wiley & Sons, Ltd.)

Objectif: Offrir aux fournisseurs de soins de maternité et à leurs patientes des lignes directrices factuelles contemporaines en ce qui concerne les services de counseling traitant des risques et des avantages maternels propres à la tenue des interventions diagnostiques prénatales orientées par échographie (et/ou des techniques permettant l'établissement d'un diagnostic génétique) nécessaires dans les cas où il a été établi pendant la période prénatale que la grossesse serait exposée à des risques, ainsi qu'en ce qui concerne la prise de décisions subséquentes quant à la prise en charge de la grossesse (questions abordant des aspects tels que le niveau du fournisseur de soins obstétricaux, la surveillance prénatale, le lieu où devraient se dérouler les soins et l'accouchement, et la décision de poursuivre ou d'interrompre la grossesse). La présente directive clinique se limite aux services de counseling traitant des risques et des avantages maternels, et aux décisions en matière de prise en charge de la grossesse pour les femmes qui nécessitent (ou qui envisagent) la mise en œuvre d'une intervention ou d'une technique effractive orientée par échographie aux fins de l'établissement d'un diagnostic prénatal., Population De Patientes: Femmes enceintes identifiées, à la suite de la mise en œuvre de protocoles établis de dépistage prénatal (taux sériques maternels ± imagerie, résultats d'analyse de l'ADN acellulaire indiquant des risques élevés, résultats anormaux au moment de l'imagerie fœtale diagnostique ou antécédents familiaux de troubles héréditaires), comme étant exposées à un risque accru d'anomalie génétique fœtale. Ces femmes pourraient nécessiter ou demander des services de counseling au sujet des risques et des avantages pour la grossesse de la tenue d'une intervention effractive orientée par échographie visant à déterminer l'étiologie, le diagnostic, et/ou la pathologie de possibles anomalies fœtales. RéSULTATS: La littérature publiée a été récupérée par l'intermédiaire de recherches menées dans Medline, PubMed et The Cochrane Library jusqu'en juin 2014 au moyen d'un vocabulaire contrôlé (« prenatal diagnosis », « amniocentesis », « chorionic villi sampling », « cordocentesis ») et de mots clés (« prenatal screening », « prenatal genetic counselling », « post-procedural pregnancy loss rate ») appropriés. Les résultats ont été restreints aux analyses systématiques, aux études observationnelles et aux essais comparatifs randomisés / essais cliniques comparatifs publiés en anglais entre janvier 1985 et juin 2014. Les recherches ont été mises à jour de façon régulière et intégrées à la directive clinique jusqu'en juin 2014. La littérature grise (non publiée) a été identifiée par l'intermédiaire de recherches menées dans les sites Web d'organismes s'intéressant à l'évaluation des technologies dans le domaine de la santé et d'organismes connexes, dans des collections de directives cliniques, dans des registres d'essais cliniques et auprès de sociétés de spécialité médicale nationales et internationales., Valeurs: La qualité des résultats a été évaluée au moyen des critères décrits dans le rapport du Groupe d'étude canadien sur les soins de santé préventifs (Tableau 1). AVANTAGES, DéSAVANTAGES ET COûTS: Consentement éclairé de la patiente, transfert des connaissances, évaluation du risque génétique prénatal, soulagement de l'anxiété, création d'anxiété, défense des droits, compréhension du dépistage fœtal, limites du dépistage fœtal, choix en matière de prise en charge de la grossesse, complication de la grossesse ou fausse couche, soins opportuns et améliorés pour l'accouchement d'un enfant présentant une morbidité reconnue. RECOMMANDATIONS., (Copyright © 2016. Published by Elsevier Inc.)

Objective: The objective of this study is to test if chorionic villus sampling (CVS) is associated with fetal growth impairment, after controlling for maternal and fetal factors., Study Design: Case-control study of singleton fetuses whose mothers had undergone CVS (N = 442) and 2969 controls. The primary outcomes were the prevalence of birthweight < 10th centile and birthweight <3rd centile; the prevalence of preeclampsia was the secondary outcome. Tested predictors in logistic regression analysis included CVS, free beta-hCG MoMs, PAPP-A MoMs, first-trimester mean uterine artery pulsatility index (PI) z-scores, maternal height, BMI, age, and smoking., Results: The proportion of newborns with birthweight <10th centile (7.9 versus 6.2%), and <3rd centile (1.6 versus 1.1%) did not differ between the two groups. Maternal age, smoking during pregnancy, PAPP-A MoMs, and mean first-trimester uterine PI z-score were significant predictors for these outcomes. Although the prevalence of preeclampsia was higher in the CVS group (3.2 versus 1.3%, OR 2.62, 95% CI 1.41-4.89), the association was abolished in the regression analysis, in which maternal body mass index, free b-hCG levels, and mean first-trimester uterine PI z-score were the only significant predictors., Conclusions: CVS is not associated with fetal growth impairment, possibly because the resulting mechanical disruption is compensated by the developing placenta, without significantly impairing its function.

The spread of both first trimester screening for chromosomal abnormalities and the possibility to check for single gene disorders at DNA-analysis has increased the request for chorionic villus sampling (CVS) in the first trimester. In order to perform placental biopsy, two routes are possible: the transcervical (TC) and the transabdominal (TA). In early days, the trancervical technique was the most diffused, but since its introduction into clinical practice, the TA technique has become the approach of choice in detriment of the TC technique. In our institution, we have a 30-year experience in TA-CVS with more than 26 000 procedures performed. Considering the expertise and the volume of procedures undertaken at our unit, we suggest a practical guideline for novel operators in TA-CVS.

First trimester screening for fetal aneuploidies has made the implementation of diagnostic techniques essential. Chorionic villus sampling (CVS) is the method of choice for obtaining chorionic villi for molecular and cytogenetic analysis in the first trimester. Two techniques have been developed, a transcervical and a transabdominal. The selection criteria have been based historically on factors, such as placental location, parity, maternal weight and preference of the operator. In our institution, we developed an elevated level of expertise in the field of transcervical approach, resulting in good quality of samples and comparable fetal loss rate to other approaches. Despite three decades of transcervical CVS performance, little consensus in terms of its technique and clinical guidelines exists. Considering the expertise and the volume of procedures performed at our center, we suggest a practical clinical guideline for transcervical CVS.

Background: Numbers of invasive prenatal procedures are declining in response to improved aneuploidy screening methods., Objective: To assess current practice and attitudes of clinicians performing invasive prenatal diagnosis in regard to patient consent and safety, maintaining procedural competence and uptake of chromosomal microarrays (CMAs)., Methods: Anonymous online survey of the Australian Association of Obstetrical and Gynaecological Ultrasonologists conducted in March 2015., Results: The survey had a 45% response rate with 59 respondents from Australia. Of these, 34 were subspecialists in maternal fetal medicine or obstetric and gynaecological ultrasound. Fifty-six (95%) currently performed amniocentesis or chorionic villus sampling. Of these, 14 (25%) performed <25 procedures and 8 (14%) performed >150 annually, with most respondents (60%) proposing 10-25 amniocenteses/year as adequate activity to maintain their skills. The majority neither expected referrers to provide results of hepatitis B and HIV serology, nor followed up missing results. There was uncertainty regarding the procedure-related vertical transmission risk of HBV in women with high viral load, with most respondents stating they were either unsure of the risk (22%) or that the risk was unknown (30%). Fifty per cent of practitioners routinely ordered CMA after invasive testing; all recommended CMA following a diagnosis of structural abnormality., Conclusions: In a period of declining testing, many Australian specialists are performing <25 procedures annually. Consideration of the potential risks of bloodborne viruses is limited. CMAs are rapidly being incorporated into clinical practice. These data have implications for patient consent and safety, and workforce training and practice., (© 2015 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.)

This month we focus on current research in prenatal aneuploidy screening. Dr. Norton discusses five recent publications, and each is concluded with a "bottom line" that is the take-home message. The complete reference for each can be found in on this page, along with direct links to the abstracts.

Purpose: We present in this study our 10years experience in prenatal diagnosis of cystic fibrosis performed in the Tunisian population., Patients and Methods: Based on family history, 40 Tunisian couples were selected for prenatal diagnosis. Fetal DNA was isolated from amniotic fluid collected by transabdominal amniocentesis or from chronic villi by transcervical chorionic villus sampling. The genetic analysis for cystic fibrosis mutations was performed by denaturant gradient gel electrophoresis and denaturing high-pressure liquid phase chromatography. We performed microsatellites analysis by capillary electrophoresis in order to verify the absence of maternal cell contamination., Results: Thirteen fetuses were affected, 21 were heterozygous carriers and 15 were healthy with two normal alleles of CFTR gene. Ten couples opted for therapeutic abortion. The microsatellites genotyping showed the absence of contamination of the fetal DNA by maternal DNA in 93.75%., Conclusion: Our diagnostic strategy provides rapid and reliable prenatal diagnosis at risk families of cystic fibrosis., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Objective: To compare the policy of prenatal diagnosis versus first trimester screening of trisomy 21 among pregnant women of advanced age., Methods: A retrospective study was conducted on patients aged ≥35 divided in two groups: patients who requested first trimester combined test and only in case of screen-positive result underwent invasive testing (group A); patients undergoing chorionic villous sampling or amniocentesis as first investigation (group B). The following outcome variables were compared: antenatal detection of trisomy 21, occurrence of trisomy 21 at birth, miscarriage rate, hospitals' costs., Results: 4527 women were included. Of these, 534 (11.80%) underwent T21 screening whereas 3993 (88.20%) requested primary invasive testing. In group A, 64 combined test were positive (11.99%) and 8 trisomy 21 cases were diagnosed (1.50%); the loss of euploid fetuses after invasive procedure was 4.55% (2/44). No false-negative case was observed. In group B 57 cases of trisomy 21 were diagnosed (1.43%), and pregnancy loss rate of chromosomally normal fetuses was 0.45% (17/3806). The estimated cost was, respectively, 67.720€ for the primary screening versus 1.996.500€ for direct prenatal diagnosis., Conclusion: First trimester screening of trisomy 21 is highly accurate and cost saving among women ≥35.