Non-invasive Prenatal Testing Research Articles

Prenatal chromosomal microarray analysis and karyotyping in fetuses with isolated choroid plexus cyst: A retrospective case-control study

ObjectivesTo evaluate the the diagnostic yield of chromosomal microarray analysis (CMA) in fetuses with isolated CPC (iCPC). MethodsA total of 315 fetuses with iCPC (iCPC group) and 364 fetuses without abnormal ultrasound findings (control group) were recruited between July 2014 to March 2018. ResultsThe overall diagnostic yield of chromosomal abnormalities by CMA and karyotyping in iCPC group was up to 4.1 %, higher than 1.4 % in the control group, p < 0.05. The detection rate of pathogenic or likely pathogenic copy number variants (CNVs) with clinical significance by CMA in iCPC group (1.3 %) was higher than in control group (0 %), p < 0.05. According to the type of chromosome abnormalities, the missed diagnosis rate of non-invasive prenatal testing (NIPT) was 1.6 % in our study. ConclusionsThe presence of iCPC on ultrasound examination suggests a potential indication for genetic counseling. Karyotyping and chromosomal microarray analysis may be considered for fetuses with iCPC. It is important to be aware of the limitations of non-invasive prenatal testing, as there is a possibility of residual risk.

Non-invasive prenatal test identifies circulating cell-free DNA chromosomal abnormalities derived from clonal hematopoiesis in aggressive hematological malignancies

Liquid biopsy is a minimally invasive diagnostic tool for identification of tumor-related mutations in circulating cell-free DNA (cfDNA). The aim of this study was to investigate feasibility, sensitivity, and specificity of non-invasive prenatal test (NIPT) for identification of chromosomal abnormalities in cfDNA from a total of 77 consecutive patients with non-Hodgkin B-cell lymphomas, Hodgkin lymphoma (HL), or plasma cell dyscrasia. In this case series, half of patients had at least one alteration, more frequently in chromosome 6 (23.1%), chromosome 9 (20.5%), and chromosomes 3 and 18 (16.7%), with losses of chromosome 6 and gains of chromosome 7 negatively impacting on overall survival (OS), with a 5-year OS of 26.9% and a median OS of 14.6 months, respectively (P = 0.0009 and P = 0.0004). Moreover, B-cell lymphomas had the highest NIPT positivity, especially those with aggressive lymphomas, while patients with plasma cell dyscrasia with extramedullary disease had a higher NIPT positivity compared to conventional cytogenetics analysis and a worse outcome. Therefore, we proposed a NIPT-based liquid biopsy a complementary minimally invasive tool for chromosomal abnormality detection in hematological malignancies. However, prospective studies on larger cohorts are needed to validate clinical utility of NIPT-based liquid biopsy in routinely clinical practice.

Decoding Promises and Perceptions: A Reflexive Thematic Analysis of the Online Presentation of Noninvasive Prenatal Testing (NIPT) in Top U.S. Brands

Due to recent news coverage of noninvasive prenatal testing (NIPT) technology, in combination with an increase in political rhetoric around women’s reproductive health and choice, I explore how language is used for promotional materials of the top 10 NIPT brands in the U.S. and convey dominant/hegemonic messages of comfort, confidence, and trustworthiness despite concerns about NIPT technology. A reflexive thematic analysis showed patterns of reliance on discourses on motherhood, parenting, and reproduction to advertise products and, conversely, a lack of the “full picture” of prenatal testing on company websites. From these results, we can gather that the potential interpretation of the website language could have more significant implications, like the premature termination of pregnancies, the increased chance of depression, and over-reliance on health information listed on the Internet. Ultimately, the language on NIPT company websites may influence decision-making and reinforce the more “powerful” messages that could potentially harm women.

Approach and Management of Pregnancies with Risk Identified by Non-Invasive Prenatal Testing.

This study represents our second investigation into NIPT, involving a more extensive patient cohort with a specific emphasis on the high-risk group. The high-risk group was subsequently divided into two further groups to compare confirmed cases versus unconfirmed via direct methods. The methodology encompassed the analysis of 1400 consecutive cases from a single genetic center in western Romania, where NIPT was used to assess the risk of specific fetal chromosomal abnormalities. All high-risk cases underwent validation through direct analysis of fetal cells obtained via invasive methods, including chorionic villus sampling and amniocentesis. The confirmation process utilized QF-PCR, karyotyping, and SNP-Array methods customized to each case. Results: A high risk of aneuploidy at NIPT was identified in 36 out of 1400 (2.57%) cases and confirmed in 28 cases. The study also detected an increased risk for copy number variations (CNVs) in 1% of cases, confirmed in two instances involving one large microdeletion and one large microduplication. Trisomy 21 was the exclusive anomaly where NIPT confirmed all cases with identified risk. High-risk NIPT results which were not validated by invasive methods, were classified as false positives; parents in these cases determined to continue the pregnancy. In conclusion, NIPT can serve as a screening method for all pregnancies; however, in high-risk cases, an invasive confirmation test is strongly recommended.

Understanding the Awareness of Prenatal Genetic Screening Tests Among Pregnant Women in India: A Cross-Sectional Study.

Introduction Genetic disorders pose a significant health challenge in India, with chromosomal abnormalities ranking second only to congenital anomalies in terms of disease burden. Prenatal testing offers a crucial strategy for identifying and managing these disorders. However, the awareness and understanding of prenatal screening tests among pregnant women in India remain understudied. This study aims to fill this gap by investigating the awareness quotient of prenatal screening tests for genetic disorders among pregnant women in India. Methods A hospital-based cross-sectional study was conducted at the Genetics Unit, Department of Anatomy, and Department of Obstetrics and Gynecology, All India Institute of Medical Sciences, Mangalagiri. Ethical clearance was obtained, and data were collected using a self-administered questionnaire covering demographic characteristics and awareness assessment. Descriptive statistics, chi-square tests, and logistic regression analysis were employed for data analysis. Results Among the 200 pregnant women surveyed, the majority demonstrated inadequate awareness of prenatal screening tests for genetic disorders, with only 36.5% possessing adequate knowledge. Significant associations were found between awareness levels and factors such as age, trimester of pregnancy, and education level. Notably, awareness about non-invasive prenatal testing (NIPT) was notably low at 7%, indicating a need for targeted educational interventions. Comparison with international studies revealed varying levels of awareness across different populations, highlighting the influence of socio-cultural factors and healthcare systems. Conclusion This study underscores the need for improved awareness of prenatal screening tests among pregnant women in India. Addressing disparities in awareness, particularly among younger age groups and those with lower education levels, is crucial for informed decision-making in prenatal care. Targeted educational interventions can empower pregnant women to make informed choices, ultimately contributing to better maternal and child health outcomes. Further research should explore the effectiveness of such interventions in diverse settings to enhance prenatal care delivery.

From Conception to Revelation: Non-Invasive Prenatal Testing Explored

Prenatal testing plays a crucial role in addressing the inherent unpredictability of genetic disorders that can affect unborn children. Non-Invasive Prenatal Testing (NIPT) has emerged as a groundbreaking tool in the realm of prenatal care, enabling the early detection of chromosomal abnormalities. By examining fetal DNA present in the mother's bloodstream, NIPT has achieved remarkable accuracy rates, surpassing invasive techniques that carry inherent risks. However, with these advancements come ethical considerations. The results of NIPT can significantly influence a mother's decision regarding the continuation or termination of pregnancy. This decision can be further complicated by religious beliefs, which often play a pivotal role in guiding choices related to pregnancy. Moreover, receiving a positive result from NIPT can subject expectant mothers to profound emotional stress, highlighting the need for comprehensive counseling and support services. In addition to these ethical concerns, practical limitations persist. The cost of NIPT remains a substantial barrier for many families, potentially limiting its accessibility. Furthermore, NIPT's accuracy can be influenced by factors such as gestational age, with tests often yielding inconclusive results when fetal fractions are low. Despite these challenges, technological innovations, including microarrays and Next Generation Sequencing (NGS), have bolstered the capabilities of NIPT. These advancements enable a more comprehensive assessment of fetal DNA, enhancing the overall quality of prenatal care. As NIPT continues to evolve and integrate with broader genomic technologies, society must engage in thoughtful reflection on its implications. The potential normalization of pregnancy terminations based on genetic information underscores the importance of ethical and societal discussions surrounding the use of NIPT, with a focus on preserving informed patient choices and ensuring comprehensive support for expectant parents facing difficult decisions.

Use of cell-free non-invasive prenatal testing in pregnancies affected by placental mosaicism.

To evaluate cell-free non-invasive prenatal testing (cfNIPT) in pregnancies affected by mosaicism. We assessed paired cfNIPT and chorionic villus sample (CVS) results from the same pregnancies in a case series of mosaicism detected in Central and North Denmark Regions from April 2014 to September 2018. Indications for the clinically obtained CVS, pregnancy markers and outcome were retrieved from The Danish Fetal Medicine Database. Mosaicisms in CVS involved common aneuploidy, n=14; sex chromosomal aneuploidies, n=14; rare autosomal trisomies (RATs), n=16 and copy number variants (CNVs) >5Mb, n=9. Overall, 24/53 (45.3%; CI 95%: 31.8%-59.4%) of cases with mosaicism were detected by cfNIPT; highest for RATs (56%) and lowest for CNVs (22%). CfNIPT more commonly detected high-level than low-level mosaic cases (p=0.000). CfNIPT detected 7/16 (43.8%; CI 95%: 21%-69%) clinically significant mosaic cases, either true fetal mosaicism or confined placental mosaicisms with adverse pregnancy outcome. There was a trend toward a higher risk for adverse outcome in pregnancies where mosaicism was detected by cfNIPT compared to pregnancies where mosaicism was not detected by cfNIPT (p=0.31). CfNIPT has a low detection rate of mosaicism, including pregnancies with clinically significant mosaicism. However, abnormal cfNIPT results may be a predictor of adverse pregnancy outcomes.

A noninvasive prenatal test pipeline with a well-generalized machine-learning approach for accurate fetal trisomy detection using low-depth short sequence data

Noninvasive prenatal test (NIPT) reduces the associated risk of procedure-related miscarriage. However, due to accuracy, special fetuses, economic and policy gaps, NIPT still cannot replace traditional surgical methods. Developing a pipeline with low cost, low technical difficulty, stability and high accuracy is a major challenge for NIPT to be widely used. This study proposes a new pipeline for the detection of fetal trisomy which includes 3 steps: 1. 40 bp single-end sequencing, 2. PchrN calculations, and 3. logisticregression (LR) models. Part of the public dataset (100 out of 144 samples) was used to train models and select features in the machine learning pipeline. 314 samples from different sources were used for independent testing. We compare the performance of our method with the bioinformatics method widely used today. Our model shows high robustness to data from different sources. The final best model achieved an AUC of 99.85 % in predicting T21 using chr21 features which are the DNA fragment concentrations. The AUC is 99.50 %, and 97.70 % in predicting T18 and T13 with all features from 24 chromosomes. The PPV of T21, T18 and T13 was predicted to be 91.67 %, 93.33 % and 83.33 %, respectively, which was higher than that obtained by standard bioinformatics methods. The NPV to identify T21, T18, and T13 were 100 %, 99.33 %, and 98.70 %, respectively. Our approach does not need to calculate fetal fraction (FF) and can handle samples from a wide range of gestational ages (GA), twin pregnancies and fetal mosaicism. Our approach can achieve comparable accuracy with the current standard bioinformatics analysis in low-depth sequencing data. This convenient pipeline can be used independently of traditional bioinformatics methods, and its performance has been tested in real clinical practice. Our pipeline can be an important aid for the detection of fetal trisomy in clinical NIPT, which will help further popularize NIPT.

Analysis of Factors Affecting Fetal Fraction in Cell-Free DNA Test

Background: Noninvasive prenatal testing (NIPT) serves as a screening method to assess the risk of chromosomal abnormalities in the fetus, including trisomy 18, 21, and 13. The reliability and success of this test are influenced by the proportion of circulating cell-free DNA obtained from the feto-placental unit, known as the fetal fraction (FF). Objectives: Our study aims to investigate the fetal and maternal factors affecting FF. Methods: Our research involved 1 150 patients referred for NIPT due to various reasons such as maternal age over 35, high-risk screening tests in the first or second trimester, history of trisomy in previous pregnancies, or patient request. Patients completed a questionnaire providing variables including maternal and fetal age, body mass index (BMI), smoking status, multiple pregnancies, and medication use such as Heparin or enoxaparin. Noninvasive prenatal testing was conducted on blood samples using Ion proton technology by Premaitha of the UK. The results, including fetal sex, trisomy risk, fetal fraction, and abnormal sex chromosomes, were analyzed using IBM SPSS 27 to assess the relationship between FF percentage and other variables. Results: The study included 1150 NIPT cases, with maternal ages ranging from 13 to 48 years, BMI from 15 to 70, and gestational age from 10 to 27 weeks. Among these, 96.4% were singleton pregnancies and 3.6% were twin pregnancies. Spontaneous pregnancies accounted for 88.9%, while 9.2% were IVF and 1.2% were IUI. Fetal sex distribution was 45.9% female and 54.1% male. FF ranged from 4% to 20.7%, with a mean FF of 11.07. No significant correlation was found between maternal age, fetal age, maternal BMI, trisomies, and FF. Conclusions: We can see that maternal age has no significant correlation with the fetal fraction. Although fetal age increases, the fetal fraction does too, but this increase was not significant. Body mass index, the route of pregnancy, and the sex of the fetus had no effect on FF. Despite NIPS being safer and yielding better results, other factors can still influence the outcomes of NIPS. Therefore, this test remains a screening tool, and clinical counseling should be conducted both before and after the test.

Supporting patient decision-making in non-invasive prenatal testing: a comparative study of professional values and practices in England and France

BackgroundNon-invasive prenatal testing (NIPT), which can screen for aneuploidies such as trisomy 21, is being implemented in several public healthcare systems across Europe. Comprehensive communication and information have been highlighted in the literature as important elements in supporting women’s reproductive decision-making and addressing relevant ethical concerns such as routinisation. Countries such as England and France are adopting broadly similar implementation models, offering NIPT for pregnancies with high aneuploidy probability. However, we do not have a deeper understanding of how professionals’ counselling values and practices may differ between these contexts.MethodsIn this paper, we explore how professionals in England and France support patient decision-making in the provision of NIPT and critically compare professional practices and values. We draw on data from semi-structured interviews with healthcare professionals.ResultsBoth English and French professionals emphasised values relating to patient choice and consent. However, understandings and application of these values into the practice of NIPT provision differed. English interviewees placed a stronger emphasis on interpreting and describing the process of counselling patients and clinical care through a “principle” lens. Their focus was on non-directiveness, standardisation, and the healthcare professional as “decision-facilitator” for patients. French interviewees described their approach through a “procedural” lens. Their focus was on formal consent, information, and the healthcare professional as “information-giver”. Both English and French professionals indicated that insufficient resources were a key barrier in effectively translating their values into practice.ConclusionOur findings illustrate that supporting patient choice in the provision of NIPT may be held as an important value in common on a surface level, but can be understood and translated into practice in different ways. Our findings can guide further research and beneficially inform practice and policy around NIPT provision.

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.

Association between fetal fraction of cell-free DNA and adverse pregnancy outcomes.

To determine the association between fetal fraction (FF) levels in cell-free fetal DNA (cffDNA) testing and adverse pregnancy outcomes. This retrospective cohort study, conducted at a single center, involved 2063 pregnant women with normal 1st and 2nd trimester non-invasive prenatal test (NIPT) results between 2016 and 2021. Pregnancy outcomes were examined by determining the < 4% and < 5th percentile (3.6%) cut-off values for low fetal fraction (LFF). Pregnancy outcomes were also examined by dividing the FF into population-based quartiles. Adverse pregnancy outcomes were pregnancy-induced hypertensive diseases (PIHD), gestational diabetes mellitus (GDM), spontaneous preterm birth (PTB), intrahepatic cholestasis of pregnancy (ICP), small for gestational age (SGA), large for gestational age (LGA), low birth weight (LBW), macrosomia, and 1st and 5th minutes low APGAR scores (< 7). PIHD was significantly higher in LFF (< 4% and < 5th percentile) cases (p = 0.015 and p < 0.001, respectively). However, in population-based quartiles of FF, PIHD did not differ significantly between groups. Composite adverse maternal outcomes were significantly higher in the FF < 4% group (p = 0.042). When analyzes were adjusted for maternal age, BMI, and gestational age at NIPT, significance was maintained at < 4%, < 5th percentile LFF for PIHD, and < 4% LFF for composite adverse maternal outcomes. However, there was no significant relationship between LFF with GDM, ICP and PTB. Additionally, there was no significant association between low APGAR scores, SGA, LGA, LBW, macrosomia, and LFF concerning neonatal outcomes. Our study showed that LFF in pregnant women with normal NIPT results may be a predictor of subsequent PIHD.

Performance Evaluation of Noninvasive Prenatal Testing in Screening Chromosome Disorders: A Single-Center Observational Study of 15,304 Consecutive Cases in China.

This study was to evaluate the performance of noninvasive prenatal testing (NIPT) in detecting fetal chromosome disorders in pregnant women. From October 1st, 2017, to December 31th, 2022, a total of 15,304 plasma cell free DNA-NIPT samples were collected for fetal chromosome disorders screening. The results of NIPT were validated by confirmatory invasive testing or clinical outcome follow-up. Further, NIPT performance between low-risk and high-risk groups, as well as singleton pregnancy and twin pregnancy groups was compared. Besides, analysis of 111 false-positive cases was performed. Totally, NIPT was performed on 15,086 eligible venous blood samples, of which 179 (1.19%) showed positive NIPT results and 68 were further validated to be true positive samples via confirmatory invasive testing or follow-up of clinical outcomes. For common chromosome aneuploidies, sex chromosome abnormalities (SCA) and other chromosomal aneuploidies, the detection sensitivities of NIPT were all 100%, the specificities were 99.87%, 99.70%, and 99.68% and the positive predictive values (PPVs) were 65.45%, 31.82%, and 10.91%, respectively. No statistically significant variance in detection performance was observed among 2987 high-risk and 12,099 low-risk subjects, as well as singleton and twin pregnancy subjects. The concentration of cell-free fetal DNA of 111 false-positive cases ranged from 5.5% to 33.7%, which was higher than the minimum requirement of NIPT. With stringent protocol, NIPT shows high sensitivity and specificity for detecting fetal chromosome disorders in a large-scale clinical service, helping improving overall pregnancy management.

Adverse pregnancy outcome in fetuses with early increased nuchal translucency: prospective cohort study.

An increased nuchal translucency (NT) thickness of ≥ 3.5 mm is a well-established marker for congenital anomalies and adverse pregnancy outcome between 11 and 14 weeks' gestation, but little is known about its performance as a screening tool before 11 weeks. We aimed to investigate, in a prospective setting, whether fetuses with increased NT before 11 weeks are at risk for adverse pregnancy outcome. This was a prospective cohort study including pregnant women with a viable fetus with NT ≥ 2.5 mm and a crown-rump length (CRL) < 45 mm. All included women were referred to our fetal medicine unit (FMU) and scheduled for a follow-up scan where the NT was remeasured after 1 week when the CRL was > 45 mm. Two groups were evaluated: cases with a normalized NT (< 3.5 mm) and cases with persistently increased NT (≥ 3.5 mm). The cases were monitored until 4 weeks after delivery. The main outcome was a composite adverse outcome of aneuploidy, other genetic disorders, structural anomalies and pregnancy loss. We performed subgroup analyses of NT thickness at inclusion and normalized or persistently increased NT at follow-up. The study included 109 cases, of which 39 (35.8%) had an adverse pregnancy outcome. Of these, 64.1% (25/39) were aneuploid, corresponding to 22.9% (25/109) of the total study population. In the subgroups of NT thickness at inclusion of 2.5-3.4 mm, 3.5-4.4 mm and ≥ 4.5 mm, an adverse outcome was reported in 22.0% (9/41), 40.0% (18/45) and 52.2% (12/23), respectively. In fetuses with a normalized NT and without ultrasound abnormalities at the follow-up scan, the incidence of adverse outcome was 8.5% (5/59), of which 5.1% (3/59) cases were aneuploid. Fetuses with an early increased NT thickness are at considerable risk of an adverse pregnancy outcome, even if the NT normalizes after 11 weeks. Not all congenital anomalies can be diagnosed with routine first-trimester screening, such as non-invasive prenatal testing and/or a first-trimester anomaly scan. Therefore, expectant parents should always be referred to a FMU for detailed ultrasonography. Invasive prenatal testing should be offered if an increased NT of ≥ 2.5 mm is observed before 11 weeks' gestation. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Noninvasive single-cell-based prenatal genetic testing: Aproof of concept clinical study.

To clinically assess a cell-based noninvasive prenatal genetic test using sequence-based copy number analysis of single trophoblasts from maternal blood. Blood was obtained from 401 (243+158) individuals (8-22weeks) and shipped overnight. Red cells were lysed, and nucleated cells stained for cytokeratin (CK) and CD45 and enriched for positive CK staining. Automated scanning was used to identify and pick single CK+ /CD45- trophoblasts which were subjected to next-generation sequencing. Blood was obtained from 243 pregnancies scheduled for CVS or amniocentesis. Luna results were normal for 160 singletons while 15 cases were abnormal (14 aneuploidy and one monozygotic twin with Williams syndrome deletion). The deletion was confirmed in both fetuses. Placental mosaicism occurred in 7 of 236 (3.0%) Luna cases and in 3 of 188 (1.6%) CVS cases (total 4.6%). No scorable trophoblasts were recovered in 32 of 236 usable samples. Additionally, 158 low-risk pregnancies not undergoing CVS/amniocentesis showed normal results in 133 cases. Seven had aneuploidy results, and there were three likely pathogenic deletions/duplications, including one15q11-q13 deletion. Although the sample size is modest and statistically accurate measures of test performance are not possible, the Luna test detected aneuploidy and deletions/duplications based on concordance with CVS/amniocentesis.

Public Opinions and Attitudes toward Noninvasive Prenatal Testing on Reddit: Content and Sentiment Analysis

Introduction: Noninvasive prenatal testing (NIPT) can be used to detect fetal chromosomal abnormalities early in pregnancy. As eligibility criteria broaden and screening targets expand, gauging public acceptability of NIPT becomes increasingly important. Leveraging social media as a rich source of public discourse, the purpose of this study was to understand public opinions and attitudes toward NIPT on the social media platform Reddit. Methods: We applied content and natural language processing techniques (i.e., sentiment analysis) to textual data collected from 4 Reddit communities focusing on the NIPT content posted from September 2012 to September 2022 (367 posts and 7,822 comments in total). Results: Content analysis findings indicated that social media users consider NIPT to be worthwhile. Reasons NIPT was perceived to be not worthwhile related to unwanted anxiety, and the fact that NIPT results would not change anything about their approach to pregnancy were also expressed. The sentiment analysis identified more positive than negative emotions; the mean sentiment scores ranged from 0.48 to 1.22, depending on the specific Lexicon used. Specific emotions (i.e., trust, fear) were also identified. Conclusion: Our novel approach to understanding public perception and attitudes toward NIPT yielded results that are consistent with conventional patient-oriented research methods. These findings may not only contribute to ongoing improvements in prenatal patient care, research, and policy but also indicate that sentiment analysis applied to social media data can serve as a suitable means to assess public acceptability of NIPT, particularly as public dialogue on this topic increases over time.

Genome-wide association and Mendelian randomisation analysis among 30,699 Chinese pregnant women identifies novel genetic and molecular risk factors for gestational diabetes and glycaemic traits

Aims/hypothesisGestational diabetes mellitus (GDM) is the most common disorder in pregnancy; however, its underlying causes remain obscure. This study aimed to investigate the genetic and molecular risk factors contributing to GDM and glycaemic traits.MethodsWe collected non-invasive prenatal test (NIPT) sequencing data along with four glycaemic and 55 biochemical measurements from 30,699 pregnant women during a 2 year period at Shenzhen Baoan Women’s and Children’s Hospital in China. Genome-wide association studies (GWAS) were conducted between genotypes derived from NIPTs and GDM diagnosis, baseline glycaemic levels and glycaemic levels after glucose challenges. In total, 3317 women were diagnosed with GDM, while 19,565 served as control participants. The results were replicated using two independent cohorts. Additionally, we performed one-sample Mendelian randomisation to explore potential causal associations between the 55 biochemical measurements and risk of GDM and glycaemic levels.ResultsWe identified four genetic loci significantly associated with GDM susceptibility. Among these, MTNR1B exhibited the highest significance (rs10830963-G, OR [95% CI] 1.57 [1.45, 1.70], p=4.42×10–29), although its effect on type 2 diabetes was modest. Furthermore, we found 31 genetic loci, including 14 novel loci, that were significantly associated with the four glycaemic traits. The replication rates of these associations with GDM, fasting plasma glucose levels and 0 h, 1 h and 2 h OGTT glucose levels were 4 out of 4, 6 out of 9, 10 out of 11, 5 out of 7 and 4 out of 4, respectively. Mendelian randomisation analysis suggested that a genetically regulated higher lymphocytes percentage and lower white blood cell count, neutrophil percentage and absolute neutrophil count were associated with elevated glucose levels and an increased risk of GDM.Conclusions/interpretationOur findings provide new insights into the genetic basis of GDM and glycaemic traits during pregnancy in an East Asian population and highlight the potential role of inflammatory pathways in the aetiology of GDM and variations in glycaemic levels.Data availabilitySummary statistics for GDM; fasting plasma glucose; 0 h, 1 h and 2h OGTT; and the 55 biomarkers are available in the GWAS Atlas (study accession no.: GVP000001, https://ngdc.cncb.ac.cn/gwas/browse/GVP000001).Graphical

Polyhydramnios associated with rare genetic syndromes: two case reports

BackgroundWe present two genetic causes of polyhydramnios that were challenging to diagnose due to their rarity and complexity. In view of the severe implications, we wish to highlight these rare genetic conditions when obstetricians consider differential diagnoses of polyhydramnios in the third trimester.Case presentationPatient 1 is a 34-year-old Asian woman who was diagnosed with polyhydramnios at 28 weeks’ gestation. First trimester testing, fetal anomaly scan, and intrauterine infection screen were normal. Subsequent antenatal ultrasound scans revealed macroglossia, raising the suspicion for Beckwith–Wiedemann syndrome. Chromosomal microarray analysis revealed a female profile with no pathological copy number variants. The patient underwent amnioreduction twice in the pregnancy. The patient presented in preterm labor at 34 weeks’ gestation but elected for an emergency caesarean section. Postnatally, the baby was noted to have a bell-shaped thorax, coat hanger ribs, hypotonia, abdominal distension, and facial dysmorphisms suggestive of Kagami–Ogata syndrome. Patient 2 is a 30-year-old Asian woman who was diagnosed with polyhydramnios at 30 weeks’ gestation. She had a high-risk first trimester screen but declined invasive testing; non-invasive prenatal testing was low risk. Ultrasound examination revealed a macrosomic fetus with grade 1 echogenic bowels but no other abnormalities. Intrauterine infection screen was negative, and there was no sonographic evidence of fetal anemia. She had spontaneous rupture of membranes at 37 + 3 weeks but subsequently delivered by caesarean section in view of pathological cardiotocography. The baby was noted to have inspiratory stridor, hypotonia, low-set ears, and bilateral toe polysyndactyly. Further genetic testing revealed a female profile with a pathogenic variant of the GLI3 gene, confirming a diagnosis of Greig cephalopolysyndactyly syndrome.ConclusionThese cases illustrate the importance of considering rare genetic causes of polyhydramnios in the differential diagnosis, particularly when fetal anomalies are not apparent at the 20-week structural scan. We would like to raise awareness for these rare conditions, as a high index of suspicion enables appropriate counseling, prenatal testing, and timely referral to pediatricians and geneticists. Early identification and diagnosis allow planning of perinatal care and birth in a tertiary center managed by a multidisciplinary team.

Usefulness of early morphological ultrasound in association with cell-free DNA testing in case of atypical serum markers in first trimester of pregnancy: A retrospective study over 5 years

BackgroundEarly morphologic ultrasound, generally carried out in case of atypical first trimester serum markers (PAPP-A and/or free hCGβ <0.30 MoM), has not been re-evaluated since the possibility of performing a cell-free fetal DNA analysis in this indication. Our objective was to evaluate the usefulness of early morphological ultrasound in case of atypical profile of serum markers performed in association with Non-Invasive Prenatal Testing (NIPT). MethodsThis was a single-center retrospective study in a tertiary maternity. Between January 2017 and December 2021, women with an atypical first trimester serum markers and low/intermediate risk for trisomy 21 (<1/50) were included. The clinical data, results of first trimester serum markers, NIPT, early morphological ultrasound and subsequent ultrasounds and other investigations (amniocentesis, pregnancy outcomes) were analyzed. ResultsAfter exclusion of women with high-risk of trisomy 21 and lost to follow-up, 163 women were included. In 72 % of cases (117/163), women had a low risk of trisomy 21, and 39 % (59/163) had an early morphological ultrasound. Early morphological ultrasound was useful to detect severe IUGR leading to the suspicion of triploidy (3/163, 1.8 %). In all other situations, it did not allow earlier management. After analysis of the 3 triploidy cases, a collapsed profile for both serum markers was demonstrated (<0.25 MoM). ConclusionsSystematic early morphological ultrasound in case of an atypical serum marker profile seems useless considering the performance of NIPT. An ultrasound restricted to women with both markers below 0.25 MoM would allow the early detection of triploidy.

Ultrasound signs of fetal chromosomal abnormalities at 11–14 weeks of pregnancy and its value in the era of modern genetic testing

A steady increase in average maternity age at the time of first childbirth lead to a higher risk of fetal chromosomal abnormalities. The Order No. 1130n of the Ministry of Health of the Russian Federation establish the screening protocol at 11–14 weeks of gestation with assessing the followed criteria of fetal chromosomal pathology: the nuchal translucency thickness, nasal bone measurement, ductus venosus pulsatility index, tricuspid regurgitation, and heart rate. The value of non-invasive prenatal testing (NIPT) in the early prenatal diagnosis of the most common chromosomal abnormalities, as the trisomies 21, 18, 13, and monosomy X is also increasing. Additionally, numerous other fetal karyotype abnormalities can also be suspected at 11–14 weeks of gestation by revealing a number of other ultrasound signs. The article presents the literature review on additional ultrasound signs of various, both more and less common, chromosomal abnormalities. Pathological signs, abnormalities of fetal anatomy and extrafetal structures in the first trimester, which could be used as additional ultrasound signs of chromosomal pathology of various organs and systems (central nervous system and head, heart and blood vessels, urinary system, abdominal organs, fetal skeleton, as well as the placenta, umbilical cord, amniotic membranes) are described in the article. Despite the use of NIPT, including its extended panels, there remains a need to use ultrasound to detect the signs of rarer, but no less significant chromosomal pathologies, such as triploidies, mosaic trisomies, rare autosomal trisomies, duplications, and deletions.