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Objective: To assess the association between body mass index (BMI) and adverse pregnancy outcomes.Materials and Methods: A multicentre retrospective cohort study was conducted in three hospitals in Hong Kong including 67,248 women with singleton pregnancy at 11-13 weeks between 2010 and 2016. The relationship between maternal BMI and (1) miscarriage or stillbirth, (2) development of preeclampsia (PE), (3) gestational hypertension (GH), (4) development of gestational diabetes mellitus (GDM), (5) spontaneous preterm delivery (sPTD) <34 and <37 weeks, (6) delivery of a small for gestational age (SGA) or large for gestational age (LGA) neonate, (7) caesarean section (CS), and (8) postpartum haemorrhage (PPH) were examined after adjusting for confounding factors.Results: The prevalence of maternal overweight (BMI 25-29.9 kg/m2) and obesity (BMI ≥30 kg/m2) were 13.2% and 2.9%, respectively. Women with a BMI ≥30 kg/m2 were nine times more likely to develop GH (95%CI 7.3-11.7), five times more likely to develop PE (95%CI 4.3-6.8) and GDM (95%CI 5.0-6.5) and 1.5-2 times more likely to deliver SGA/LGA neonate. sPTD, required delivery by CS and developed PPH, than those with a BMI of 18.5-22.9 kg/m2, and that maternal underweight (BMI <18.5 kg/m2) significantly reduced the risk of GDM, delivery by CS, and PPH. Increased risk of subsequent development of adverse outcomes was observed when BMI was ≥23.0 kg/m2.Conclusions: Maternal overweight and obesity are associated with an increased risk for subsequent development of various pregnancy complications. The need of increased awareness and health surveillance is essential when BMI ≥23 kg/m2. [ABSTRACT FROM AUTHOR]

Objective: Cell-free DNA (cfDNA) fragments in maternal plasma contain DNA damage and may negatively impact the sensitivity of noninvasive prenatal testing (NIPT). However, some of these DNA damages are potentially reparable. We aimed to recover these damaged cfDNA molecules using PreCR DNA repair mix.Methods: cfDNA was extracted from 20 maternal plasma samples and was repaired and sequenced by the Illumina platform. Size profiles and fetal DNA fraction changes of repaired samples were characterized. Targeted sequencing of chromosome Y sequences was used to enrich fetal cfDNA molecules following repair. Single-molecule real-time (SMRT) sequencing platform was employed to characterize long (>250 bp) cfDNA molecules. NIPT of five trisomy 21 samples was performed.Results: Size profiles of repaired libraries were altered, with significantly increased long (>250 bp) cfDNA molecules. Single nucleotide polymorphism (SNP)-based analyses showed that both fetal- and maternal-derived cfDNA molecules were enriched by the repair. Fetal DNA fractions in maternal plasma showed a small but consistent (4.8%) increase, which were contributed by a higher increment of long fetal cfDNA molecules. z-score values were improved in NIPT of all trisomy 21 samples.Conclusion: Plasma DNA repair recovers and enriches long cfDNA molecules of both fetal and maternal origins in maternal plasma. [ABSTRACT FROM AUTHOR]

Objective: To determine intersonographer, intersampling site pulsatility index differences in the ascending branch of the uterine artery (UtA-PI) and their effect on detection rates (DR) for early onset preeclampsia (PE).Methods: A prospective observational study was conducted including 52 women with singleton viable pregnancy at 11-13 weeks' gestation. Consecutive bilateral UtA-PI measurements were performed by two sonographers. Both sonographers hold the Fetal Medicine Foundation (FMF) uterine artery Doppler assessment competency certificates. Sonographer "A" underwent mentorship-based specialist training at the FMF; whilst sonographer "B" is a fetal maternal specialist who was deemed competent to measure UtA-PI based on completion of the FMF online course. Both sonographers were unaware of each other's UtA-PI and peak systolic velocity (PSV) measurements throughout the study. UtA-PI was measured by sonographer "A" at 1, 2 and 3 cm distally from the internal os. UtA-PI minimum ("Low-PI") and mean ("Mean-PI") were determined. Intraclass correlation (ICC), Bland-Altman analysis and Wilcoxon signed rank test were performed to determine bias, 95% limits of agreement (LOA) for intersonographer and intersampling site differences. Simulation studies were performed to determine the effect on early onset PE screening DR.Results: (1) Intersite assessment indicated that UtA-PI and PSV decreased by 7-8% per centimeter relative to the measurement taken at the internal os; (2) Sonographer "B" UtA-PI measurements were significantly lower than those of sonographer "A" for "Low-PI" (p = .001), "Mean-PI" (p = .002) and PSV (p = .004) determined by Wilcoxon signed rank test. The mean reduction in "Low-PI", "Mean-PI" and PSV of sonographer "B" relative to sonographer "A" were 14.04%, 11.09% and 10.99%, respectively; (3) Measurements taken by sonographer "B" at the level of the internal os were comparable to measurements taken by sonographer "A" at 2 cm distal to the internal os (low-PI: p = .98, Mean-PI: p = .49 and PSV: p = .24); (4) Between sonographer ICC for UtA-PI was asymmetrical strong (left ICC = 0.72, 95%CI: 0.51-0.84) to fair (right ICC = 0.38, 95%CI: -0.08-0.64); and (5) The 14% mean intersonographer difference in lowest UtA-PI would have resulted in an 7% difference in PE screening performance.Conclusions: The measurement of UtA-PI is sampling site dependent with the potential for significant intersonographer differences despite the availability of a prescriptive measurement protocol. This is an important observation as it implies that sonographer "B" inadvertently measured the UtA-PI at a distal site, not at the level of internal os, compared to those measured by sonographer "A", resulting in a lower DR for early onset PE. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: First-trimester cervical length for the prediction of spontaneous preterm delivery remains controversial. A better method for the measurement of the first-trimester cervical length and additional cervical ultrasound parameters for the identification of women at high risk for spontaneous preterm delivery are needed.Objective: This study aimed to compare the predictive value of cervical length measured by 2 different methods in the first trimester of pregnancy to predict spontaneous preterm delivery and to explore the potential value of first-trimester cervical shear-wave elastography for the prediction of spontaneous preterm delivery.Study Design: This was a prospective study in unselected singleton pregnancies at 11+0 to 13+6 weeks' gestation. Cervical length was measured by the following 2 methods in the base-cohort population: (1) a linear distance between the 2 ends of the glandular area around the endocervical canal (single-line method: cervical length-s) and (2) a sum of the linear distance from the internal os to the greatest cervical curvature and the linear distance from this point to the external os (2-line method: cervical length-t). In a substudy, cervical shear-wave elastography scores for 9 regions of interest (inner, middle, and external parts of anterior lip, endocervical canal, and posterior lip) in midsagittal plane were also obtained by transvaginal ultrasonography. The screening performance of the first-trimester cervical length measured by the 2 different methods for the prediction of spontaneous preterm delivery was assessed by receiver operating characteristics curve analysis. The areas under the curves were compared using a DeLong test. The predictive performance of a soft cervix (mean elastography scores with multiple of median <5th, 10th, 15th, 20th, and 25th percentile) for spontaneous preterm delivery was also determined.Results: Among a total of 2316 included pregnancies, spontaneous delivery at <37 and <34 weeks' gestation occurred in 111 cases (4.8%) and 20 cases (0.9%), respectively. In the total study population, when compared with the term delivery group, the median cervical length-t was shorter in women with spontaneous delivery at <34 weeks' gestation (36.9 mm vs 35.1 mm; P=.015), but there was no clear correlation for cervical length-s. Receiver operating characteristics curves demonstrated that cervical length-t achieved better performance in predicting spontaneous delivery at <34 weeks' gestation (area under the curve, 0.658 vs 0.573; P<.01) than cervical length-s. The best combined model to predict spontaneous delivery at <34 weeks' gestation was provided by cervical length-t and history of preterm delivery (area under the curve, 0.692). In the substudy, a soft cervix with a mean elastography scores multiple of median <10th percentile had a relative risk of 7.8 (95% confidence interval, 2.1-28.6) for spontaneous delivery at <34 weeks' gestation; the detection rate was 44.4% at a false-positive rate of 9.0%.Conclusion: The 2-line approach provides a better estimate of the actual first-trimester cervical length and achieves better performance as a screening tool for spontaneous preterm delivery at <34 weeks' gestation than the conventional measurement. A soft cervix as determined by shear-wave elastograpthy in the first trimester is associated with an increased risk for subsequent spontaneous preterm delivery. [ABSTRACT FROM AUTHOR]

The averaged incidences of nonsyndromal/isolated cleft lip (CL), cleft palate (CP), and cleft lip with cleft palate (CLCP) by each month-of-conception, and managed in our hospital in from 2002 to 2009 were correlated with the reported levels of sunshine, ultraviolet radiation, and ambient nitrogen oxides (nitrogen oxide, nitrogen monoxide, and nitrogen dioxide), sulfur dioxide, and ozone, at the month of, and then at 4 and 8 weeks after, conception. There were 25, 12, and 22 cases each of CL, CP, and CLCP, respectively, totaling 59 cases (1.21 of 1000 births). On regression analysis, sunshine correlated inversely with the isolated CL at (P = .009) 4 weeks (P = .005) and 8 weeks (P = .008) postconception, and with CP (P = .009) and CLCP (P < .001) at 8 weeks postconception, while NOx correlated inversely with CL (P = .018) and NO with CLCP (P = .031), at 8 weeks postconception. Our results suggested that the interaction between sunshine and nitrogen oxides with other factors results in the reported seasonal variation in the incidence of isolated oral-facial clefts. [ABSTRACT FROM AUTHOR]

Objectives. To study the perinatal outcome among monochorionic diamniotic (MCDA) twin pregnancies with absent or reversed end-diastolic flow of the umbilical artery (UA-AREDF) at 16-20 weeks of gestation. Methods. This was a retrospective study of 84 MCDA twin pregnancies, which were followed up since first trimester in a single obstetric unit. Pregnancies with fetal structural anomalies or genetic syndromes, and those with single intrauterine death before 16 weeks were excluded. The study group was divided into four groups based on the finding of UA-AREDF at the routine follow-up scan at 16-20 week, and the presence of complications at the same time of recruitment. The perinatal outcome between these groups was compared. Results. AREDF was present in 56.7%% of the 30 monochorionic (MC) twins with complications at recruitment. The mortality was significantly higher among those with AREDF. Among the 54 uncomplicated cases at recruitment, only 7.41%% had AREDF. The presence of isolated AREDF was associated with significantly higher incidence of growth discordance (25.0%% vs. 2%%). The incidence of perinatal mortality and twin-to-twin transfusion syndrome was almost doubled (25.0%% vs. 9%% and 25.0%% vs. 14%%). Conclusions. AREDF of the umbilical artery is uncommon in normal MC twin in mid-trimester. Once AREDF is present, the perinatal outcome is much worse. Doppler assessment of the umbilical artery should be considered in all MC twin pregnancies for risk assessment. [ABSTRACT FROM AUTHOR]

Nausea and vomiting in pregnancy (NVP) is the most common pregnancy complication affecting women during the first trimester of pregnancy. The cause of NVP remains unknown and factors associated with the occurrence of NVP are contradictory. There is currently little information on its effects of NVP in general and specifically in the Chinese population. To assess the prevalence of NVP with different degree of severity and identify their relationship with health-related quality of life (HRQoL) and to determine its association with the sociodemographic and obstetric factors. In a prospective cross-sectional study, 396 women who attended the antenatal clinic between 10 and 14 weeks of gestation were invited to complete a structured questionnaire covering maternal characteristics, severity of NVP and their HRQoL. The status of NVP and HRQoL was measured by the frequency of symptoms and the Medical Outcomes Study Short-Form-36 (SF-36) respectively. Logistic regression analysis was performed to delineate the factors associated with NVP. The prevalence of NVP was 90.9%. Almost all domains and dimensions of SF-36 were affected by the presence of NVP and its severity. Factors associated with the presence and severity of NVP were non-smoking, younger age and history of NVP in previous pregnancy. The various degrees of severity of NVP significantly impair both physical and mental HRQoL in Hong Kong Chinese women. Awareness and care should be given to women with symptoms of nausea or retching alone, as well as vomiting. [ABSTRACT FROM AUTHOR]

Objective. To examine the effectiveness of first trimester fetal Trisomy 21 (T21) screening using a combination of maternal age, nuchal translucency, maternal serum levels of free β-hCG and PAPP-A in a predominantly Chinese population in Hong Kong. Methods. Consecutive women who underwent the combined screening for T21 between 11 and 13 + 6 weeks of gestation between 2003 and 2007 were recruited. Risk of T21 was calculated using Fetal Medicine Foundation algorithm and karyotyping was advised when the risk was 1:300 or above. All women were followed up for pregnancy and fetal outcome. Results. 10,363 fetuses underwent screening. 99% of the women were Chinese and 27.4% were at or above 35 years old. 618 fetuses were screened positive (5.9%), which included 31 cases of T21, 14 cases of T18, 7 cases of T13, 10 cases of 45XO and 7 cases of other chromosomal abnormalities. Among the 9745 screened negative fetuses all but 50 (0.5%) had a known outcome, which included three T21 and four other chromosomal abnormalities. All were subsequently identified at the morphology scan except for one case of T21. The detection rate and false positive rates for T21 were 91.2% and 5.4%, respectively and the positive predictive value for all chromosomal abnormalities was 1 in 9. Conclusions. Combined screening for T21 is highly effective among Chinese women. Training, quality control, regular auditing and follow up are essential to maintain screening standards. [ABSTRACT FROM AUTHOR]

Objective: The objective of the study was to determine the likelihood ratio for trisomy 21 in Chinese fetuses with absent nasal bone (NB) at 11-14 weeks of gestation. Study Design: The NB was classified as present or absent in 8101 chromosomally/phenotypically normal or trisomy 21 pregnancies. The effect of crown rump length (CRL), nuchal translucency (NT), maternal age, and fetal karyotype on the incidence of absent NB was examined using logistic regression. Results: The NB was successfully examined in 7925 cases (97.8%). The incidence of absent NB in unaffected and trisomy 21 cases were 2.1% (164/7899) and 50% (13/26), respectively. CRL (odds ratio [OR], 0.9; 95% confidence interval [CI], 0.87-0.92), NT (OR, 1.7; 95% CI, 1.4-2.3), and trisomy 21 (OR, 22.3; 95% CI, 8.1-61) were significant independent predictors of likelihood of absent NB. Positive likelihood ratios (LR) for trisomy 21 in Chinese were lower than that of Caucasians for the equivalent CRL and NT measurements. Conclusion: Estimated risk for trimsomy 21 in Chinese incorporating nasal bone status should use LRs derived in Chinese rather than Caucasians. [Copyright &y& Elsevier]

Abstract: Objective: To compare seroprevalence (serum IgG titre) with self-reported history of varicella zoster virus (VZV) infection among pregnant women in Hong Kong. Methods: Pregnant women undergoing first trimester Down screening over a 3-months period were recruited for the study. Results: Positive immunity was found in 477 (95.4%) of the 500 recruited women, and those with positive, negative, or uncertain history of infection had similarly high seroprevalence (96.4, 90.5, 95.9% respectively). The mean age of infection from self-recalled history was 8.61 (SD 4.69) years, and only 3% recalled infection after age 18. Insufficient knowledge on the disease and vaccination was demonstrated. Conclusions: Despite the absence of a routine vaccination programme, VZV immunity was high among pregnant women, the majority being infected during childhood and infection above age 18 was very rare. Hence, universal antenatal screening or vaccination for all women in the reproductive age would not be cost-effective in Hong Kong. [Copyright &y& Elsevier]