Prospective observations study protocol to investigate cost-effectiveness of various prenatal test strategies after the introduction of noninvasive prenatal testing

Prenatal diagnosis, pregnancy determination and follow up of sex chromosome aneuploidy screened by non-invasive prenatal testing from 122 453 unselected singleton pregnancies: A retrospective analysis of 7-year experience

The phenotype of SCA patients are diversities, make prenatal counseling and parental decision-making following the prenatal diagnosis of SCA more complicated and challenging. NIPT has higher sensitivity and specificity in screening trisomy 21 syndrome, but the effectiveness of NIPT in detecting SCA is still controversial. This study is a large-scale retrospective cohort of positive SCA screened from unselected singleton pregnancies by non-invasive prenatal testing (NIPT) from a single prenatal center of a tertiary hospital. Clinical information, indications, diagnostic results, ultrasound findings, pregnancy determinations, and follow-up were reviewed and analyzed. 596 cases of SCA positive were screened out of 122 453, giving a positive detection rate of 0.49%. 510 cases (85.6%) conducted with amniocentesis to detect fetal chromosome, of which 236 were confirmed as true positive of SCA with PPV of 46.3% (236/510). Of the 236 cases confirmed as true positive SCA, 114 cases (48.3%)chose to terminate the pregnancy (93.0%, 65.3%, 15.4% and 10.9% for 45,X, 47,XXY, 47,XXX and 47,XYY, respectively), 122 cases (51.7%) elected to continue the pregnancy. In conclusions, NIPT as a first-tier routine method for screening autosomal aneuploidies, also could play an important role in screening SCA. Low-risk pregnant women are the main indication for the detection of SCA as NIPT test provides to non-selective population. For 47,XXX and 47,XYY with mild phenotype, couples would like to continue the pregnancy. But for 45,X and 47,XXY, parents apt to terminate pregnancy no matter ultrasound abnormalities were found or not.

Adverse outcomes in subsequent pregnancies in women with history of recurrent spontaneous abortion: A meta-analysis

OBJECTIVE

This study aimed to investigate the association between a history of recurrent spontaneous abortion (RSA) and adverse outcomes in women with spontaneous conception.

METHODS

A search strategy from the inception to March 3, 2023 was run in PubMed, Embase, Cochrane Library, and Web of Science databases. The odds ratio (OR), and the 95% confidence interval (CI) or point estimation were used as the evaluation indexes. Each outcome measure tested was assessed for heterogeneity using the Cochran Q test. Sensitivity analyses were performed to test the credibility of the meta-analysis results.

RESULTS

Fifteen studies involving 1 475 389 pregnant women were included. A history of RSA was associated with gestational diabetes (OR: 2.21, 95% CI: 1.70-2.87, p < 0.001), preeclampsia (OR: 2.06, 95% CI: 1.49-2.86, p < 0.001), placenta previa (OR: 1.82, 95% CI: 1.09-3.02, p = 0.021), placental abruption (OR: 1.67, 95% CI: 1.36-2.06, p < 0.001), miscarriage (OR: 6.37, 95% CI: 3.83-10.57, p < 0.001), preterm birth (OR: 1.80, 95% CI: 1.36-2.37, p < 0.001), cesarean section (OR: 1.47, 95% CI: (1.13-1.91, p = 0.004), perinatal death (OR: 2.24, 95% CI: 1.39-3.60, p = 0.001), and neonatal intensive care unit admission (OR: 1.39, 95% CI: 1.01-1.92, p = 0.047). However, the associations of a history of RSA with gestational hypertension, small for gestational age, fetal anomalies, fetal growth restriction, and postpartum hemorrhage were not observed.

CONCLUSION

This meta-analysis indicates a history of RSA was associated with increased risks of several adverse outcomes in pregnant women with spontaneous conception.

The Effect of Vanishing Twin on First- and Second-Trimester Maternal Serum Markers and Nuchal Translucency: A Multicenter Prospective Cohort Study

BACKGROUND

The purpose of this study was to evaluate the effect of vanishing twin (VT) on maternal serum marker concentrations and nuchal translucency (NT).

METHODS

This is a secondary analysis of a multicenter prospective cohort study in 12 institutions. Serum concentrations of pregnancy-associated plasma protein-A in the first trimester and alpha-fetoprotein (AFP), total human chorionic gonadotrophin, unconjugated estriol, and inhibin A in the second trimester were measured, and NT was measured between 10 and 14 weeks of gestation.

RESULTS

Among 6,793 pregnant women, 5,381 women were measured for serum markers in the first or second trimester, including 65 cases in the VT group and 5,316 cases in the normal singleton group. The cases in the VT group had a higher median multiple of the median value of AFP and inhibin A than the normal singleton group. The values of other serum markers and NT were not different between the two groups. After the permutation test with adjustment, AFP and inhibin A remained significant differences. The frequency of abnormally increased AFP was also higher in the VT group than in the normal singleton group.

CONCLUSION

VT can be considered as an adjustment factor for risk assessment in the second-trimester serum screening test.

Chromosomal Abnormality, fetal/neonatal Death and Socioeconomic Status: A Prospective Cohort Study

OBJECTIVES

To assess the risk gradient of chromosomal abnormalities and fetal or neonatal death across a socioeconomic spectrum of pregnant women.

METHODS

We used the data from the Korean Prenatal Diagnosis Study (KPDS), which included singleton pregnancies who were candidates for fetal aneuploidy screening enrolled from the Seoul Capital Area from December 2016 to April 2018. We analyzed chromosomal abnormalities which were diagnosed pre- or postnatally, and fetal or neonatal death. The highest level of education among the women and the average monthly household income were used as proxies for socioeconomic status.

RESULTS

Among the 6,715 women, the majority of were 30-39 years old and university graduates, with a reported household income higher than the national median. Chromosomal abnormalities occurred in 45 women (6.7 per 1,000). Fetal or neonatal death occurred in 70 (11.3 per 1,000), excluding pregnancies affected by chromosomal abnormality diagnosis. The adjusted odds ratio for chromosomal abnormalities was higher when household income was < 4,484 USD per month. For fetal or neonatal death, the risk estimates for lower education and lower household income were generally positive but remained imprecise.

CONCLUSION

We observed some evidence of an inverse association between the risk of fetal chromosomal abnormality and level of household income in a prospective cohort of pregnant women. Interventions to reduce socioeconomic disparities in perinatal health should focus on those with a low household income.

Prenatal Diagnosis of Congenital Heart Diseases and Associations with Serum Biomarkers of Aneuploidy: A Multicenter Prospective Cohort Study

PURPOSE

We assessed prenatal detection rates of congenital heart disease (CHD) and associations between maternal serum biomarkers and non-chromosomal CHD in singleton pregnancies.

MATERIALS AND METHODS

This study was conducted as a secondary analysis of data obtained during a multicenter prospective cohort study that investigated the cost-effectiveness of prenatal testing for fetal aneuploidy. We analyzed the prenatal detection rate and accuracy for CHD screening via ultrasound during the second trimester, as well as associations between serum biomarkers and CHDs, in singleton newborns without chromosomal abnormalities.

RESULTS

Among 6715 women, 142 (2.1%) newborns were born with CHDs, of which 67 (1.0%) newborns had major CHDs. The prenatal detection rate for all CHDs and major CHDs were 34.5% and 58.2%, respectively. After excluding isolated ventricular septal defects, the detection rate for critical CHDs was 85.9%. Women with low pregnancy-associated plasma protein A (PAPP-A) (<0.4 multiples of the median, MOM) face increased risks of non-chromosomal CHDs [adjusted odds ratio (aOR) 2.76; 95% confidence interval (CI) 1.36-5.13] and major CHDs (aOR 7.30; 95% CI 3.18-15.59), compared to those without CHDs. A higher inhibin A level (≥2.5 MOM; aOR 4.84; 95% CI 1.42-12.46) was associated with non-chromosomal major CHDs.

CONCLUSION

Ultrasonography performed during the second trimester by obstetricians detected over 85% of critical CHDs. Low maternal serum PAPP-A or high inhibin-A was associated with non-chromosomal CHDs. These results may contribute to an improvement in prenatal diagnosis of CHDs.

The screening of diagnostic biomarker microRNA in first-trimester maternal plasma for Down syndrome: A study protocol

BACKGROUND

The trisomy of human chromosome 21 causes Down syndrome (DS), sometimes known as congenital folly's syndrome. The survivors show apparent mental impairment, unusual facial traits, growth and development abnormalities, and various deformities, with 60 percent of the infants having miscarriages in the early stages of the fetus. Plasma micRNA (miRNA) is a new diagnostic biomarker for DS; however, its significance in first-trimester maternal plasma is unknown. As a result, the purpose of this study is to assess the diagnostic significance of the biomarker miRNA in first-trimester maternal plasma for DS.

MATERIALS AND METHODS

From January 2014 until the present, blood samples were obtained from pregnant women who visited our hospital. This study included 20 eligible DS pregnancies and 20 normal pregnant women. We looked at the differential miRNA expression profile in DS maternal plasma from the first and second trimesters using miRNA microarrays. Bioinformatics technology was used to compare the particular miRNA in DS maternal plasma from the first and second trimesters and screen the miRNA co-expressed in DS maternal plasma. Meanwhile, the expression level of chosen miRNAs was verified using quantitative real-time PCR (qRT-PCR).

DISCUSSION

This study aims to see how useful the diagnostic biomarker miRNA in first-trimester maternal plasma is for diagnosing DS. The findings of this investigation will provide clinical evidence for the discovery of a new diagnostic biomarker miRNA in first-trimester maternal plasma for DS diagnosis.

OSF REGRESSION NUMBER

DOI 10.17605/OSF.IO/R49FT.

Validation of a Strict Obesity Definition Proposed for Asians to Predict Adverse Pregnancy Outcomes in Korean Pregnant Women

BACKGROUND

People are generally considered overweight and obese if their body mass index (BMI) is above 25 kg/m² and 30.0 kg/m², respectively. The World Health Organization proposed stricter criteria for Asians (≥ 23 kg/m²: overweight, ≥ 25 kg/m²: obese). We aimed to verify whether this criteria could predict adverse pregnancy outcomes in Korean women.

METHODS

We included 7,547 Korean women from 12 institutions enrolled between June 2016 and October 2018. Women with no pre-pregnancy BMI data, not Korean, or lost to follow-up were excluded, leaving 6,331. The subjects were categorized into underweight, normal, overweight, class I obesity, and class II/III obesity based on a pre-pregnancy BMI of < 18.5, 18.5-22.9, 23.0-24.9, 25.0-29.9, and ≥ 30.0 kg/m², respectively.

RESULTS

Overall, 13.4%, 63.0%, 11.8%, 9.1%, and 2.6% of women were underweight, normal, and overweight and had class I obesity and class II/III obesity, respectively. In the multivariable analysis adjusted for maternal age, a higher BMI significantly increased the risk of preeclampsia, gestational diabetes, preterm delivery caused by maternal-fetal indications, cesarean section, large for gestational age, and neonatal intensive care unit admission.

CONCLUSION

Adverse pregnancy outcomes started to increase in those with a pre-pregnancy BMI ≥ 23.0 kg/m² after adjusting for maternal age. The modified obesity criteria could help predict adverse pregnancy outcomes in Koreans.

The risk of preterm birth in vanishing twin: A multicenter prospective cohort study

Objective

To evaluate not only the risk of total preterm birth (PTB) but also spontaneous preterm birth (sPTB) and indicated preterm birth (iPTB) in vanishing twin (VT).

Study design

This is a secondary analysis of a multicenter prospective cohort study. In 12 different healthcare institutions, women with singleton pregnancies were enrolled in early pregnancy and followed up till delivery.

Results

A total of 4,746 women were included in the final analysis, and. the frequency of VT was 1.1% (54/4746). VT group had a higher risk for total PTB (PTB<34 weeks, 2.1% vs. 14.8%, p<0.001; PTB<32 weeks, 1.6% vs. 13.0%, p<0.001; PTB<28 weeks, 0.9% vs. 13.0%, p<0.001) than singleton group. The VT group had increased risk for both sPTB and iPTB (<34 weeks, <32 weeks, and <28 weeks), and this increased risk for sPTB and iPTB in VT group remained significant even after controlling for confounders such as maternal age, parity, pre-pregnancy BMI, and mode of conception.

Conclusion

Vanishing twin can be an independent risk factor for both sPTB and iPTB when compared with singleton pregnancy.

Clinical performance of non-invasive prenatal testing for trisomies 21, 18 and 13 in twin pregnancies: A cohort study and a systematic meta-analysis

INTRODUCTION

The objective of this study was to report on the clinical performance of non-invasive prenatal testing (NIPT) for trisomies 21, 18 and 13 in twin pregnancies and to define the performance of NIPT by combining our cohort study results with published studies in a systematic meta-analysis.

MATERIAL AND METHODS

A cohort study was carried out in the First Affiliated Hospital of Sun Yat-sen University and Kanghua Hospital. Meanwhile, searches of PubMed, EMBASE, The Cochrane Library and Web of Science for all relevant peer-reviewed articles were performed with a restriction to English language publication before 15 June 2019. Quality assessments were conducted with the Quality Assessment Tool for Diagnostic Accuracy Studies-2 checklist. Data analysis, heterogeneity, subgroup analysis and publication bias were carried out using META-DISC 1.4 and STATA 12.0.

RESULTS

In all, 141 twin pregnancies included in our cohort study; confirmation revealed one true-positive case for trisomy 21 and 140 true-negative cases. The sensitivity and specificity for trisomy 21 by NIPT were both 100%. Twenty-two eligible studies were enrolled in this meta-analysis together with our study. There were 199 cases of trisomy 21, 58 cases of trisomy 18, 14 cases of trisomy 13 and 6347 cases of euploids in total. For trisomy 21, NIPT showed the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio were 0.99, 1.00, 145.81, 0.06 and 1714.09, respectively. For trisomy 18, the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio were 0.88, 1.00, 200.98, 0.19 and 483.68, respectively.

CONCLUSIONS

The performance of NIPT for trisomy 21 in twin pregnancy was excellent and it was similar to that reported in singleton pregnancy. However, due to publication bias (trisomy 18) and small number of cases (trisomy 13), accurate assessment of the predictive performance of NIPT for trisomies 18 and 13 could not be achieved.

Non-invasive cell-free fetal DNA testing for aneuploidy: multicenter study of 31 515 singleton pregnancies in southeastern China

OBJECTIVE

To analyze the non-invasive prenatal testing (NIPT) for aneuploidy results of 31 515 singleton pregnancies in Fujian province, southeastern China, and assess its performance in low-, moderate- and high-risk pregnancies.

METHODS

Women were categorized into groups according to whether their risk for fetal abnormality was low, moderate or high. Cell-free plasma DNA extracted from peripheral blood samples was subjected to low-coverage whole-genome sequencing. Standard Z-score analysis of the mapped sequencing reads was used to identify fetal aneuploidy, including the three main trisomies (T21, T18 and T13) and sex chromosome aneuploidy (SCA). NIPT-positive results were confirmed by amniocentesis and karyotyping. The performance of NIPT for detection of T21, T18, T13 and SCA was assessed by calculating the sensitivity and specificity.

RESULTS

The rate of chromosomal abnormality detected by NIPT in the study population was 1.38%. A higher rate of chromosomal abnormality was found in the high-risk group (1.57%) compared to the moderate-risk (1.05%) and low-risk (1.18%) groups (P < 0.05). Sensitivity and specificity, respectively, were 98.96% (95/96) and 99.94% (31 274/31 292) for detection of T21, 100% (25/25) and 99.96% (31 352/31 363) for T18, 100% (7/7) and 99.97% (31 373/31 381) for T13 and 100% (61/61) and 99.74% (31 245/31 327) for SCA. Positive predictive values were high for T21 (84.07%) and T18 (69.44%) and moderate for T13 (46.67%) and SCA (42.66%).

CONCLUSION

Our findings support the application of NIPT for reliable and accurate testing of the general population of reproductive-age women for clinically significant fetal aneuploidy. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

A two-year experience of non-invasive prenatal testing (NIPT) at an urban tertiary medical center in South Korea

OBJECTIVE

To report our experience of implementing non-invasive prenatal testing (NIPT) in a tertiary urban academic medical center in South Korea.

MATERIALS AND METHODS

An observational retrospective study of singleton and twin pregnancies that underwent prenatal screening for fetal aneuploidy from July 2016 to April 2018 was conducted. Demographics of the study population electing NIPT versus those opting the integrated test were compared. We also assessed clinical significant factors influencing cfDNA fetal fraction in NIPT.

RESULTS

Among the 817 women who underwent serum screening tests during the study period, 490 women (60.0%) chose the integrated test while 327 women (40.0%) chose NIPT. Compared to the integrated test group, women in the NIPT group were older (mean age 34.7 ± 3.7 vs. 32.6 ± 3.4; p-value < 0.01), multiparous (47.1% vs. 39.8%; p-value = 0.046), and had higher rate of previous abortion history (28.4% vs. 21.6%; p-value = 0.033). A significant decrease in the number of invasive diagnostic tests was observed since the adoption of NIPT. The screen negative and positive rates of the integrated test group for fetal aneuploidy were 95.3% and 4.7%, respectively while those of the NIPT group were 95.9% and 1.2%, respectively. The rate of inadequate cfDNA fetal fraction was 3.0%. Low fetal fraction was associated with higher maternal age, body weight and BMI.

CONCLUSIONS

The implementation of NIPT has significantly affected the practice pattern of prenatal aneuploidy screening by replacing the integrated test and decreasing invasive diagnostic tests.