Systematic evaluation of genome sequencing for the diagnostic assessment of autism spectrum disorder and fetal structural anomalies.

Short-read genome sequencing (GS) holds the promise of becoming the primary diagnostic approach for the assessment of autism spectrum disorder (ASD) and fetal structural anomalies (FSAs). However, few studies have comprehensively evaluated its performance against current standard-of-care diagnostic tests: karyotype, chromosomal microarray (CMA), and exome sequencing (ES). To assess the clinical utility of GS, we compared its diagnostic yield against these three tests in 1,612 quartet families including an individual with ASD and in 295 prenatal families. Our GS analytic framework identified a diagnostic variant in 7.8% of ASD probands, almost 2-fold more than CMA (4.3%) and 3-fold more than ES (2.7%). However, when we systematically captured copy-number variants (CNVs) from the exome data, the diagnostic yield of ES (7.4%) was brought much closer to, but did not surpass, GS. Similarly, we estimated that GS could achieve an overall diagnostic yield of 46.1% in unselected FSAs, representing a 17.2% increased yield over karyotype, 14.1% over CMA, and 4.1% over ES with CNV calling or 36.1% increase without CNV discovery. Overall, GS provided an added diagnostic yield of 0.4% and 0.8% beyond the combination of all three standard-of-care tests in ASD and FSAs, respectively. This corresponded to nine GS unique diagnostic variants, including sequence variants in exons not captured by ES, structural variants (SVs) inaccessible to existing standard-of-care tests, and SVs where the resolution of GS changed variant classification. Overall, this large-scale evaluation demonstrated that GS significantly outperforms each individual standard-of-care test while also outperforming the combination of all three tests, thus warranting consideration as the first-tier diagnostic approach for the assessment of ASD and FSAs.

Comparing population-based fetal growth standards in a US cohort.

BACKGROUND: No fetal growth standard is currently endorsed for universal use in the United States. Newer standards improve upon the methodologic limitations of older studies; however, before adopting into practice, it is important to know how recent standards perform at identifying fetal undergrowth or overgrowth and at predicting subsequent neonatal morbidity or mortality in US populations. OBJECTIVE: To compare classification of estimated fetal weight that is <5th or 10th percentile or >90th percentile by 6 population-based fetal growth standards and the ability of these standards to predict a composite of neonatal morbidity and mortality. STUDY DESIGN: We used data from the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-be cohort, which recruited nulliparous women in the first trimester at 8 US clinical centers (2010-2014). Estimated fetal weight was obtained from ultrasounds at 16 to 21 and 22 to 29 weeks of gestation (N=9534 women). We calculated rates of fetal growth restriction (estimated fetal weight <5th and 10th percentiles; fetal growth restriction<5 and fetal growth restriction<10) and estimated fetal weight >90th percentile (estimated fetal weight>90) from 3 large prospective fetal growth cohorts with similar rigorous methodologies: INTERGROWTH-21, World Health Organization-sex-specific and combined, Eunice Kennedy Shriver National Institute of Child Health and Human Development race-ethnic-specific and unified, and the historic Hadlock reference. To determine whether differential classification of fetal growth restriction or estimated fetal weight >90 among standards was clinically meaningful, we then compared area under the curve and sensitivity of each standard to predict small for gestational age or large for gestational age at birth, composite perinatal morbidity and mortality alone, and small for gestational age or large for gestational age with composite perinatal morbidity and mortality. RESULTS: The standards classified different proportions of fetal growth restriction and estimated fetal weight>90 for ultrasounds at 16 to 21 (visit 2) and 22 to 29 (visit 3) weeks of gestation. At visit 2, the Eunice Kennedy Shriver National Institute of Child Health and Human Development race-ethnic-specific, World Health Organization sex-specific and World Health Organization-combined identified similar rates of fetal growth restriction<10 (8.4%-8.5%) with the other 2 having lower rates, whereas Eunice Kennedy Shriver National Institute of Child Health and Human Development race-ethnic-specific identified the highest rate of fetal growth restriction<5 (5.0%) compared with the other references. At visit 3, World Health Organization sex-specific classified 9.2% of fetuses as fetal growth restriction<10, whereas the other 5 classified a lower proportion as follows: World Health Organization-combined (8.4%), Eunice Kennedy Shriver National Institute of Child Health and Human Development race-ethnic-specific (7.7%), INTERGROWTH (6.2%), Hadlock (6.1%), and Eunice Kennedy Shriver National Institute of Child Health and Human Development unified (5.1%). INTERGROWTH classified the highest (21.3%) as estimated fetal weight>90 whereas Hadlock classified the lowest (8.3%). When predicting composite perinatal morbidity and mortality in the setting of early-onset fetal growth restriction, World Health Organization had the highest area under the curve of 0.53 (95% confidence interval, 0.51-0.53) for fetal growth restriction<10 at 22 to 29 weeks of gestation, but the areas under the curve were similar among standards (0.52). Sensitivity was generally low across standards (22.7%-29.1%). When predicting small for gestational age birthweight with composite neonatal morbidity or mortality, for fetal growth restriction<10 at 22 to 29 weeks of gestation, World Health Organization sex-specific had the highest area under the curve (0.64; 95% confidence interval, 0.60-0.67) and INTERGROWTH had the lowest (area under the curve=0.58; 95% confidence interval 0.55-0.62), though all standards had low sensitivity (7.0%-9.6%). CONCLUSION: Despite classifying different proportions of fetuses as fetal growth restriction or estimated fetal weight>90, all standards performed similarly in predicting perinatal morbidity and mortality. Classification of different percentages of fetuses as fetal growth restriction or estimated fetal weight>90 among references may have clinical implications in the management of pregnancies, such as increased antenatal monitoring for fetal growth restriction or cesarean delivery for suspected large for gestational age. Our findings highlight the importance of knowing how standards perform in local populations, but more research is needed to determine if any standard performs better at identifying the risk of morbidity or mortality.

The role of cell-free DNA biomarkers and patient data in the early prediction of preeclampsia: an artificial intelligence model.

BACKGROUND: Accurate individualized assessment of preeclampsia risk enables the identification of patients most likely to benefit from initiation of low-dose aspirin at 12 to 16 weeks of gestation when there is evidence for its effectiveness, and enables the guidance of appropriate pregnancy care pathways and surveillance. OBJECTIVE: The primary objective of this study was to evaluate the performance of artificial neural network models for the prediction of preterm preeclampsia (<37 weeks' gestation) using patient characteristics available at the first antenatal visit and data from prenatal cell-free DNA screening. Secondary outcomes were prediction of early-onset preeclampsia (<34 weeks' gestation) and term preeclampsia (≥37 weeks' gestation). METHODS: This secondary analysis of a prospective, multicenter, observational prenatal cell-free DNA screening study (SMART) included singleton pregnancies with known pregnancy outcomes. Thirteen patient characteristics that are routinely collected at the first prenatal visit and 2 characteristics of cell-free DNA (total cell-free DNA and fetal fraction) were used to develop predictive models for early-onset (<34 weeks), preterm (<37 weeks), and term (≥37 weeks) preeclampsia. For the models, the "reference" classifier was a shallow logistic regression model. We also explored several feedforward (nonlinear) neural network architectures with ≥1 hidden layers, and compared their performance with the logistic regression model. We selected a simple neural network model built with 1 hidden layer and made up of 15 units. RESULTS: Of the 17,520 participants included in the final analysis, 72 (0.4%) developed early-onset, 251 (1.4%) preterm, and 420 (2.4%) term preeclampsia. Median gestational age at cell-free DNA measurement was 12.6 weeks, and 2155 (12.3%) had their cell-free DNA measurement at ≥16 weeks' gestation. Preeclampsia was associated with higher total cell-free DNA (median, 362.3 vs 339.0 copies/mL cell-free DNA; P<.001) and lower fetal fraction (median, 7.5% vs 9.4%; P<.001). The expected, cross-validated area under the curve scores for early-onset, preterm, and term preeclampsia were 0.782, 0.801, and 0.712, respectively, for the logistic regression model, and 0.797, 0.800, and 0.713, respectively, for the neural network model. At a screen-positive rate of 15%, sensitivity for preterm preeclampsia was 58.4% (95% confidence interval, 0.569-0.599) for the logistic regression model and 59.3% (95% confidence interval, 0.578-0.608) for the neural network model. The contribution of both total cell-free DNA and fetal fraction to the prediction of term and preterm preeclampsia was negligible. For early-onset preeclampsia, removal of the total cell-free DNA and fetal fraction features from the neural network model was associated with a 6.9% decrease in sensitivity at a 15% screen-positive rate, from 54.9% (95% confidence interval, 52.9-56.9) to 48.0% (95% confidence interval, 45.0-51.0). CONCLUSION: Routinely available patient characteristics and cell-free DNA markers can be used to predict preeclampsia with performance comparable to that of other patient characteristic models for the prediction of preterm preeclampsia. Logistic regression and neural network models showed similar performance.

Amniocentesis in pregnancies at or beyond 24 weeks: an international multicenter study.

BACKGROUND: Amniocentesis for genetic diagnosis is most commonly done between 15 and 22 weeks of gestation but can be performed at later gestational ages. The safety and genetic diagnostic accuracy of amniocentesis have been well-established through numerous large-scale multicenter studies for procedures before 24 weeks, but comprehensive data on late amniocentesis remain sparse. OBJECTIVE: To evaluate the indications, diagnostic yield, safety, and maternal and fetal outcomes associated with amniocentesis performed at or beyond 24 weeks of gestation. STUDY DESIGN: We conducted an international multicenter retrospective cohort study examining pregnant individuals who underwent amniocentesis for prenatal diagnostic testing at gestational ages between 24w0d and 36w6d. The study, spanning from 2011 to 2022, involved 9 referral centers. We included singleton or twin pregnancies with documented outcomes, excluding cases where other invasive procedures were performed during pregnancy or if amniocentesis was conducted for obstetric indications. We analyzed indications for late amniocentesis, types of genetic tests performed, their results, and the diagnostic yield, along with pregnancy outcomes and postprocedure complications. RESULTS: Of the 752 pregnant individuals included in our study, late amniocentesis was primarily performed for the prenatal diagnosis of structural anomalies (91.6%), followed by suspected fetal infection (2.3%) and high-risk findings from cell-free DNA screening (1.9%). The median gestational age at the time of the procedure was 28w5d, and 98.3% of pregnant individuals received results of genetic testing before birth or pregnancy termination. The diagnostic yield was 22.9%, and a diagnosis was made 2.4 times more often for fetuses with anomalies in multiple organ systems (36.4%) compared to those with anomalies in a single organ system (15.3%). Additionally, the diagnostic yield varied depending on the specific organ system involved, with the highest yield for musculoskeletal anomalies (36.7%) and hydrops fetalis (36.4%) when a single organ system or entity was affected. The most prevalent genetic diagnoses were aneuploidies (46.8%), followed by copy number variants (26.3%) and monogenic disorders (22.2%). The median gestational age at delivery was 38w3d, with an average of 59 days between the procedure and delivery date. The overall complication rate within 2 weeks postprocedure was 1.2%. We found no significant difference in the rate of preterm delivery between pregnant individuals undergoing amniocentesis between 24 and 28 weeks and those between 28 and 32 weeks, reinforcing the procedure's safety across these gestational periods. CONCLUSION: Late amniocentesis, at or after 24 weeks of gestation, especially for pregnancies complicated by multiple congenital anomalies, has a high diagnostic yield and a low complication rate, underscoring its clinical utility. It provides pregnant individuals and their providers with a comprehensive diagnostic evaluation and results before delivery, enabling informed counseling and optimized perinatal and neonatal care planning.

Multiethnic growth standards for fetal body composition and organ volumes derived from 3D ultrasonography.

BACKGROUND: A major goal of contemporary obstetrical practice is to optimize fetal growth and development throughout pregnancy. To date, fetal growth during prenatal care is assessed by performing ultrasonographic measurement of 2-dimensional fetal biometry to calculate an estimated fetal weight. Our group previously established 2-dimensional fetal growth standards using sonographic data from a large cohort with multiple sonograms. A separate objective of that investigation involved the collection of fetal volumes from the same cohort. OBJECTIVE: The Fetal 3D Study was designed to establish standards for fetal soft tissue and organ volume measurements by 3-dimensional ultrasonography and compare growth trajectories with conventional 2-dimensional measures where applicable. STUDY DESIGN: The National Institute of Child Health and Human Development Fetal 3D Study included research-quality images of singletons collected in a prospective, racially and ethnically diverse, low-risk cohort of pregnant individuals at 12 U.S. sites, with up to 5 scans per fetus (N=1730 fetuses). Abdominal subcutaneous tissue thickness was measured from 2-dimensional images and fetal limb soft tissue parameters extracted from 3-dimensional multiplanar views. Cerebellar, lung, liver, and kidney volumes were measured using virtual organ computer aided analysis. Fractional arm and thigh total volumes, and fractional lean limb volumes were measured, with fractional limb fat volume calculated by subtracting lean from total. For each measure, weighted curves (fifth, 50th, 95th percentiles) were derived from 15 to 41 weeks' using linear mixed models for repeated measures with cubic splines. RESULTS: Subcutaneous thickness of the abdomen, arm, and thigh increased linearly, with slight acceleration around 27 to 29 weeks. Fractional volumes of the arm, thigh, and lean limb volumes increased along a quadratic curvature, with acceleration around 29 to 30 weeks. In contrast, growth patterns for 2-dimensional humerus and femur lengths demonstrated a logarithmic shape, with fastest growth in the second trimester. The mid-arm area curve was similar in shape to fractional arm volume, with an acceleration around 30 weeks, whereas the curve for the lean arm area was more gradual. The abdominal area curve was similar to the mid-arm area curve with an acceleration around 29 weeks. The mid-thigh and lean area curves differed from the arm areas by exhibiting a deceleration at 39 weeks. The growth curves for the mid-arm and thigh circumferences were more linear. Cerebellar 2-dimensional diameter increased linearly, whereas cerebellar 3-dimensional volume growth gradually accelerated until 32 weeks followed by a more linear growth. Lung, kidney, and liver volumes all demonstrated gradual early growth followed by a linear acceleration beginning at 25 weeks for lungs, 26 to 27 weeks for kidneys, and 29 weeks for liver. CONCLUSION: Growth patterns and timing of maximal growth for 3-dimensional lean and fat measures, limb and organ volumes differed from patterns revealed by traditional 2-dimensional growth measures, suggesting these parameters reflect unique facets of fetal growth. Growth in these three-dimensional measures may be altered by genetic, nutritional, metabolic, or environmental influences and pregnancy complications, in ways not identifiable using corresponding 2-dimensional measures. Further investigation into the relationships of these 3-dimensional standards to abnormal fetal growth, adverse perinatal outcomes, and health status in postnatal life is warranted.

Improving prenatal diagnosis through standards and aggregation.

Advances in sequencing and imaging technologies enable enhanced assessment in the prenatal space, with a goal to diagnose and predict the natural history of disease, to direct targeted therapies, and to implement clinical management, including transfer of care, election of supportive care, and selection of surgical interventions. The current lack of standardization and aggregation stymies variant interpretation and gene discovery, which hinders the provision of prenatal precision medicine, leaving clinicians and patients without an accurate diagnosis. With large amounts of data generated, it is imperative to establish standards for data collection, processing, and aggregation. Aggregated and homogeneously processed genetic and phenotypic data permits dissection of the genomic architecture of prenatal presentations of disease and provides a dataset on which data analysis algorithms can be tuned to the prenatal space. Here we discuss the importance of generating aggregate data sets and how the prenatal space is driving the development of interoperable standards and phenotype-driven tools.

The expanded spectrum of human disease associated with GREB1L likely includes complex congenital heart disease.

OBJECTIVE: GREB1L has been linked prenatally to Potter's sequence, as well as less severe anomalies of the kidney, uterus, inner ear, and heart. The full phenotypic spectrum is unknown. The purpose of this study was to characterize known and novel pre- and postnatal phenotypes associated with GREB1L. METHODS: We solicited cases from the Fetal Sequencing Consortium, screened a population-based genomic database, and conducted a comprehensive literature search to identify disease cases associated with GREB1L. We present a detailed phenotypic spectrum and molecular changes. RESULTS: One hundred twenty-seven individuals with 51 unique pathogenic or likely pathogenic GREB1L variants were identified. 24 (47%) variants were associated with isolated kidney anomalies, 19 (37%) with anomalies of multiple systems, including one case of hypoplastic left heart syndrome, five (10%) with isolated sensorineural hearing loss, two (4%) with isolated uterine agenesis; and one (2%) with isolated tetralogy of Fallot. CONCLUSION: GREB1L may cause complex congenital heart disease (CHD) in humans. Clinicians should consider GREB1L testing in the setting of CHD, and cardiac screening in the setting of GREB1L variants.

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

OBJECTIVE: To clinically assess a cell-based noninvasive prenatal genetic test using sequence-based copy number analysis of single trophoblasts from maternal blood. METHODS: Blood was obtained from 401 (243 + 158) individuals (8-22 weeks) 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. RESULTS: 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. CONCLUSION: 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.

Monogenic conditions and central nervous system anomalies: A prospective study, systematic review and meta-analysis.

OBJECTIVES: Determine the incremental diagnostic yield of prenatal exome sequencing (pES) over chromosome microarray (CMA) or G-banding karyotype in fetuses with central nervous system (CNS) abnormalities. METHODS: Data were collected via electronic searches from January 2010 to April 2022 in MEDLINE, Cochrane, Web of Science and EMBASE. The NHS England prenatal exome cohort was also included. Incremental yield was calculated as a pooled value using a random-effects model. RESULTS: Thirty studies were included (n = 1583 cases). The incremental yield with pES for any CNS anomaly was 32% [95%CI 27%-36%; I2 = 72%]. Subgroup analysis revealed apparent incremental yields in; (a) isolated CNS anomalies; 27% [95%CI 19%-34%; I2 = 74%]; (b) single CNS anomaly; 16% [95% CI 10%-23%; I2 = 41%]; (c) more than one CNS anomaly; 31% [95% Cl 21%-40%; I2 = 56%]; and (d) the anatomical subtype with the most optimal yield was Type 1 malformation of cortical development, related to abnormal cell proliferation or apoptosis, incorporating microcephalies, megalencephalies and dysplasia; 40% (22%-57%; I2 = 68%). The commonest syndromes in isolated cases were Lissencephaly 3 and X-linked hydrocephalus. CONCLUSIONS: Prenatal exome sequencing provides a high incremental diagnostic yield in fetuses with CNS abnormalities with optimal yields in cases with multiple CNS anomalies, particularly those affecting the midline, posterior fossa and cortex.

Effect of an Intrapartum Pelvic Dilator Device on Levator Ani Muscle Avulsion During Primiparous Vaginal Delivery: A Pilot Randomized Controlled Trial.

INTRODUCTION AND HYPOTHESIS: The objective was to evaluate the safety and effectiveness of an intrapartum electromechanical pelvic floor dilator designed to reduce the risk of levator ani muscle (LAM) avulsion during vaginal delivery. METHODS: A multicenter, randomized controlled trial enrolled nulliparous participants planning vaginal delivery. During the first stage of labor, participants were randomized to receive the intravaginal device or standard-of-care labor management. The primary effectiveness endpoint was the presence of full LAM avulsion on transperineal pelvic-floor ultrasound at 3 months. Three urogynecologists performed blinded interpretation of ultrasound images. The primary safety endpoint was adverse events (AEs) through 3 months. RESULTS: A total of 214 women were randomized to Device (n = 113) or Control (n = 101) arms. Of 113 Device assignees, 82 had a device placed, of whom 68 delivered vaginally. Of 101 Control participants, 85 delivered vaginally. At 3 months, 110 participants, 46 Device subjects who received full device treatment, and 64 Controls underwent ultrasound for the per-protocol analysis. No full LAM avulsions (0.0%) occurred in the Device group versus 7 out of 64 (10.9%) in the Control group (p = 0.040; two-tailed Fisher's test). A single maternal serious AE (laceration) was device related; no neonate serious AEs were device related. CONCLUSIONS: The pelvic floor dilator device significantly reduced the incidence of complete LAM avulsion in nulliparous individuals undergoing first vaginal childbirth. The dilator demonstrated an acceptable safety profile and was well received by recipients. Use of the intrapartum electromechanical pelvic floor dilator in laboring nulliparous individuals may reduce the rate of LAM avulsion, an injury associated with serious sequelae including pelvic organ prolapse.

Association of Mild Iodine Insufficiency during Pregnancy with Child Neurodevelopment in Patients with Subclinical Hypothyroidism or Hypothyroxinemia.

OBJECTIVE: Our objective was to evaluate whether iodine status in pregnant patients with either subclinical hypothyroidism or hypothyroxinemia in the first half of pregnancy is associated with measures of behavior and neurodevelopment in children through the age of 5 years. STUDY DESIGN: This is a secondary analysis of a multicenter study consisting of two randomized, double-masked, placebo-controlled treatment trials conducted in parallel. Patients with a singleton gestation before 20 weeks' gestation underwent thyroid screening using serum thyrotropin and free thyroxine. Participants with subclinical hypothyroidism or hypothyroxinemia were randomized to levothyroxine replacement or an identical placebo. At randomization, maternal urine was collected and stored for subsequent urinary iodine excretion analysis. Urinary iodine concentrations greater than 150 µg/L were considered iodine sufficient, and concentrations of 150 µg/L or less were considered iodine insufficient. The primary outcome was a full-scale intelligence quotient (IQ) score at the age of 5 years, the general conceptual ability score from the Differential Ability Scales-II at the age of 3 if IQ was not available, or death before 3 years. RESULTS: A total of 677 pregnant participants with subclinical hypothyroidism and 526 with hypothyroxinemia were randomized. The primary outcome was available in 1,133 (94%) of children. Overall, 684 (60%) of mothers were found to have urinary iodine concentrations >150 µg/L. Children of iodine-sufficient participants with subclinical hypothyroidism had similar primary outcome scores when compared to children of iodine-insufficient participants (95 [84-105] vs. 96 [87-109], P adj = 0.73). After adjustment, there was also no difference in IQ scores among children of participants with hypothyroxinemia at 5 to 7 years of age (94 [85 - 102] and 91 [81 - 100], Padj 1/4 0.11). Treatment with levothyroxine was not associated with neurodevelopmental or behavioral outcomes regardless of maternal iodine status (p > 0.05). CONCLUSION: Maternal urinary iodine concentrations ≤150 µg/L were not associated with abnormal cognitive or behavioral outcomes in offspring of participants with either subclinical hypothyroidism or hypothyroxinemia. KEY POINTS: · Most pregnant patients with subclinical thyroid disease are iodine sufficient.. · Mild maternal iodine insufficiency is not associated with lower offspring IQ at 5 years.. · Iodine supplementation in subclinical thyroid disease is unlikely to improve IQ..

Fetal and Maternal Factors Predictive of Primary Cesarean Delivery at Term in a Low-Risk Population: NICHD Fetal Growth Studies-Singletons.

OBJECTIVE: This study aimed to examine associations of fetal biometric and amniotic fluid measures with intrapartum primary cesarean delivery (PCD) and develop prediction models for PCD based on ultrasound parameters and maternal factors. STUDY DESIGN: Secondary analysis of the National Institute of the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) Fetal Growth Studies-singleton cohort (2009-2013) including patients with uncomplicated pregnancies and intent to deliver vaginally at ≥370/7 weeks. The estimated fetal weight, individual biometric parameters, fetal asymmetry measurements, and amniotic fluid single deepest vertical pocket assessed at the final scan (mean 37.5 ± 1.9 weeks) were categorized as <10th, 10th to 90th (reference), and >90th percentiles. Logistic regression analyses examined the association between the ultrasound measures and PCD. Fetal and maternal SuperLearner prediction algorithms were constructed for the full and nulliparous cohorts. RESULTS: Of the 1,668 patients analyzed, 249 (14.9%) had PCD. The fetal head circumference, occipital-frontal diameter, and transverse abdominal diameter >90th percentile (adjusted odds ratio [aOR] = 2.50, 95% confidence interval [95% CI]: 1.39, 4.51; aOR = 1.86, 95% CI: 1.02, 3.40; and aOR = 2.13, 95% CI: 1.16, 3.89, respectively) were associated with PCD. The fetal model demonstrated poor ability to predict PCD in the full cohort and in nulliparous patients (area under the receiver-operating characteristic curve [AUC] = 0.56, 95% CI: 0.52, 0.61; and AUC = 0.54, 95% CI: 0.49, 0.60, respectively). Conversely, the maternal model had better predictive capability overall (AUC = 0.79, 95% CI: 0.75, 0.82) and in the nulliparous subgroup (AUC = 0.72, 95% CI: 0.67, 0.77). Models combining maternal/fetal factors performed similarly to the maternal model (AUC = 0.78, 95% CI: 0.75, 0.82 in full cohort, and AUC = 0.71, 95% CI: 0.66, 0.76 in nulliparas). CONCLUSION: Although a few fetal biometric parameters were associated with PCD, the fetal prediction model had low performance. In contrast, the maternal model had a fair-to-good ability to predict PCD. KEY POINTS: · Fetal HC >90th percentile was associated with cesarean delivery.. · Fetal parameters did not effectively predict PCD.. · Maternal factors were more predictive of PCD.. · Maternal/fetal and maternal models performed similarly.. · Prediction models had lower performance in nulliparas..

Causal Genetic Variants in Stillbirth.

BACKGROUND: In the majority of cases, the cause of stillbirth remains unknown despite detailed clinical and laboratory evaluation. Approximately 10 to 20% of stillbirths are attributed to chromosomal abnormalities. However, the causal nature of single-nucleotide variants and small insertions and deletions in exomes has been understudied. METHODS: We generated exome sequencing data for 246 stillborn cases and followed established guidelines to identify causal variants in disease-associated genes. These genes included those that have been associated with stillbirth and strong candidate genes. We also evaluated the contribution of 18,653 genes in case-control analyses stratified according to the degree of depletion of functional variation (described here as "intolerance" to variation). RESULTS: We identified molecular diagnoses in 15 of 246 cases of stillbirth (6.1%) involving seven genes that have been implicated in stillbirth and six disease genes that are good candidates for phenotypic expansion. Among the cases we evaluated, we also found an enrichment of loss-of-function variants in genes that are intolerant to such variation in the human population (odds ratio, 2.15; 95% confidence interval [CI], 1.46 to 3.06). Loss-of-function variants in intolerant genes were concentrated in genes that have not been associated with human disease (odds ratio, 2.22; 95% CI, 1.41 to 3.34), findings that differ from those in two postnatal clinical populations that were also evaluated in this study. CONCLUSIONS: Our findings establish the diagnostic utility of clinical exome sequencing to evaluate the role of small genomic changes in stillbirth. The strength of the novel risk signal (as generated through the stratified analysis) was similar to that in known disease genes, which indicates that the genetic cause of stillbirth remains largely unknown. (Funded by the Institute for Genomic Medicine.).

Performance of prenatal cfDNA screening for sex chromosomes.

PURPOSE: The aim of this study was to assess the performance of cell-free DNA (cfDNA) screening to detect sex chromosome aneuploidies (SCAs) in an unselected obstetrical population with genetic confirmation. METHODS: This was a planned secondary analysis of the multicenter, prospective SNP-based Microdeletion and Aneuploidy RegisTry (SMART) study. Patients receiving cfDNA results for autosomal aneuploidies and who had confirmatory genetic results for the relevant sex chromosomal aneuploidies were included. Screening performance for SCAs, including monosomy X (MX) and the sex chromosome trisomies (SCT: 47,XXX; 47,XXY; 47,XYY) was determined. Fetal sex concordance between cfDNA and genetic screening was also evaluated in euploid pregnancies. RESULTS: A total of 17,538 cases met inclusion criteria. Performance of cfDNA for MX, SCTs, and fetal sex was determined in 17,297, 10,333, and 14,486 pregnancies, respectively. Sensitivity, specificity, and positive predictive value (PPV) of cfDNA were 83.3%, 99.9%, and 22.7% for MX and 70.4%, 99.9%, and 82.6%, respectively, for the combined SCTs. The accuracy of fetal sex prediction by cfDNA was 100%. CONCLUSION: Screening performance of cfDNA for SCAs is comparable to that reported in other studies. The PPV for the SCTs was similar to the autosomal trisomies, whereas the PPV for MX was substantially lower. No discordance in fetal sex was observed between cfDNA and postnatal genetic screening in euploid pregnancies. These data will assist interpretation and counseling for cfDNA results for sex chromosomes.

Mouse and human studies support DSTYK loss of function as a low-penetrance and variable expressivity risk factor for congenital urinary tract anomalies.

PURPOSE: Previous work identified rare variants in DSTYK associated with human congenital anomalies of the kidney and urinary tract (CAKUT). Here, we present a series of mouse and human studies to clarify the association, penetrance, and expressivity of DSTYK variants. METHODS: We phenotypically characterized Dstyk knockout mice of 3 separate inbred backgrounds and re-analyzed the original family segregating the DSTYK c.654+1G>A splice-site variant (referred to as "SSV" below). DSTYK loss of function (LOF) and SSVs were annotated in individuals with CAKUT, epilepsy, or amyotrophic lateral sclerosis vs controls. A phenome-wide association study analysis was also performed using United Kingdom Biobank (UKBB) data. RESULTS: Results demonstrate ∼20% to 25% penetrance of obstructive uropathy, at least, in C57BL/6J and FVB/NJ Dstyk-/- mice. Phenotypic penetrance increased to ∼40% in C3H/HeJ mutants, with mild-to-moderate severity. Re-analysis of the original family segregating the rare SSV showed low penetrance (43.8%) and no alternative genetic causes for CAKUT. LOF DSTYK variants burden showed significant excess for CAKUT and epilepsy vs controls and an exploratory phenome-wide association study supported association with neurological disorders. CONCLUSION: These data support causality for DSTYK LOF variants and highlights the need for large-scale sequencing studies (here >200,000 cases) to accurately assess causality for genes and variants to lowly penetrant traits with common population prevalence.

Obstetrical, perinatal, and genetic outcomes associated with nonreportable prenatal cell-free DNA screening results.

BACKGROUND: The clinical implications of nonreportable cell-free DNA screening results are uncertain, but such results may indicate poor placental implantation in some cases and be associated with adverse obstetrical and perinatal outcomes. OBJECTIVE: This study aimed to assess the outcomes of pregnancies with nonreportable cell-free DNA screening in a cohort of patients with complete genetic and obstetrical outcomes. STUDY DESIGN: This was a prespecified secondary analysis of a multicenter prospective observational study of prenatal cell-free DNA screening for fetal aneuploidy and 22q11.2 deletion syndrome. Participants who underwent cell-free DNA screening from April 2015 through January 2019 were offered participation. Obstetrical outcomes and neonatal genetic testing results were collected from 21 primary-care and referral centers in the United States, Europe, and Australia. The primary outcome was risk for adverse obstetrical and perinatal outcomes (aneuploidy, preterm birth at <28, <34, and <37 weeks' gestation, preeclampsia, small for gestational age or birthweight <10th percentile for gestational week, and a composite outcome that included preterm birth at <37 weeks, preeclampsia, small for gestational age, and stillbirth at >20 weeks) after nonreportable cell-free DNA screening because of low fetal fraction or other causes. Multivariable analyses were performed, adjusting for variables known to be associated with obstetrical and perinatal outcomes, nonreportable results, or fetal fraction. RESULTS: In total, 25,199 pregnant individuals were screened, and 20,194 were enrolled. Genetic confirmation was missing in 1165 (5.8%), 1085 (5.4%) were lost to follow-up, and 93 (0.5%) withdrew; the final study cohort included 17,851 (88.4%) participants who had cell-free DNA, fetal or newborn genetic confirmatory testing, and obstetrical and perinatal outcomes collected. Results were nonreportable in 602 (3.4%) participants. A sample was redrawn and testing attempted again in 427; in 112 (26.2%) participants, results were again nonreportable. Nonreportable results were associated with higher body mass index, chronic hypertension, later gestational age, lower fetal fraction, and Black race. Trisomy 13, 18, or 21 was confirmed in 1.6% with nonreportable tests vs 0.7% with reported results (P=.013). Rates of preterm birth at <28, 34, and 37 weeks, preeclampsia, and the composite outcome were higher among participants with nonreportable results, and further increased among those with a second nonreportable test, whereas the rate of small for gestational age infants was not increased. After adjustment for confounders, the adjusted odds ratios were 2.2 (95% confidence interval, 1.1-4.4) and 2.6 (95% confidence interval, 0.6-10.8) for aneuploidy, and 1.5 (95% confidence interval, 1.2-1.8) and 2.1 (95% confidence interval, 1.4-3.2) for the composite outcome after a first and second nonreportable test, respectively. Of the patients with nonreportable tests, 94.9% had a live birth, as opposed to 98.8% of those with reported test results (adjusted odds ratio for livebirth, 0.20 [95% confidence interval, 0.13-0.30]). CONCLUSION: Patients with nonreportable cell-free DNA results are at increased risk for a number of adverse outcomes, including aneuploidy, preeclampsia, and preterm birth. They should be offered diagnostic genetic testing, and clinicians should be aware of the increased risk of pregnancy complications.

Impact of high-risk prenatal screening results for 22q11.2 deletion syndrome on obstetric and neonatal management: Secondary analysis from the SMART study.

OBJECTIVE: One goal of prenatal genetic screening is to optimize perinatal care and improve infant outcomes. We sought to determine whether high-risk cfDNA screening for 22q11.2 deletion syndrome (22q11.2DS) affected prenatal or neonatal management. METHODS: This was a secondary analysis from the SMART study. Patients with high-risk cfDNA results for 22q11.2DS were compared with the low-risk cohort for pregnancy characteristics and obstetrical management. To assess differences in neonatal care, we compared high-risk neonates without prenatal genetic confirmation with a 1:1 matched low-risk cohort. RESULTS: Of 18,020 eligible participants enrolled between 2015 and 2019, 38 (0.21%) were high-risk and 17,982 (99.79%) were low-risk for 22q11.2DS by cfDNA screening. High-risk participants had more prenatal diagnostic testing (55.3%; 21/38 vs. 2.0%; 352/17,982, p < 0.001) and fetal echocardiography (76.9%; 10/13 vs. 19.6%; 10/51, p < 0.001). High-risk newborns without prenatal diagnostic testing had higher rates of neonatal genetic testing (46.2%; 6/13 vs. 0%; 0/51, P < 0.001), echocardiography (30.8%; 4/13 vs. 4.0%; 2/50, p = 0.013), evaluation of calcium levels (46.2%; 6/13 vs. 4.1%; 2/49, P < 0.001) and lymphocyte count (53.8%; 7/13 vs. 15.7%; 8/51, p = 0.008). CONCLUSIONS: High-risk screening results for 22q11.2DS were associated with higher rates of prenatal and neonatal diagnostic genetic testing and other 22q11.2DS-specific evaluations. However, these interventions were not universally performed, and >50% of high-risk infants were discharged without genetic testing, representing possible missed opportunities to improve outcomes for affected individuals.

Sleep-disordered Breathing in Pregnancy and after Delivery: Associations with Cardiometabolic Health.

Rationale: Knowledge gaps exist regarding health implications of sleep-disordered breathing (SDB) identified in pregnancy and/or after delivery. Objectives: To determine whether SDB in pregnancy and/or after delivery is associated with hypertension (HTN) and metabolic syndrome (MS). Methods: nuMoM2b-HHS (Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-be Heart Health Study) (N = 4,508) followed participants initially recruited during their first pregnancy. Participants returned for a visit 2-7 years after pregnancy. This study examined a subgroup who underwent SDB assessments during their first pregnancy (n = 1,964) and a repeat SDB assessment after delivery (n = 1,222). Two SDB definitions were considered: 1) apnea-hypopnea index (AHI) ⩾ 5 and 2) oxygen desaturation index (ODI) ⩾ 5. Associations between SDB and incident HTN and MS were evaluated with adjusted risk ratios (aRRs). Measurements and Main Results: The aRR for MS given an AHI ⩾ 5 during pregnancy was 1.44 (95% confidence interval [CI], 1.08-1.93), but no association with HTN was found. ODI ⩾ 5 in pregnancy was associated with both an increased risk for HTN (aRR, 2.02; 95% CI, 1.30-3.14) and MS (aRR, 1.53; 95% CI, 1.19-1.97). Participants with an AHI ⩾ 5 in pregnancy that persisted after delivery were at higher risk for both HTN (aRR, 3.77; 95% CI, 1.84-7.73) and MS (aRR, 2.46; 95% CI, 1.59-3.76). Similar associations were observed for persistent ODI ⩾ 5 after delivery. Conclusions: An AHI ⩾ 5 in pregnancy was associated with an increased risk of MS. An ODI ⩾ 5 in pregnancy was significantly associated with both HTN and MS. Participants with persistent elevations in AHI and ODI during pregnancy and at 2-7 years after delivery were at the highest risk for HTN and MS. Clinical trial registered with www.clinicaltrials.gov (NCT02231398).

Correlation of Ocular Plane-Wave Doppler With Optical Coherence Tomography Angiography in Preeclampsia.

OBJECTIVES: Preeclampsia (PE) is a severe complication of pregnancy characterized by hypertension, proteinuria and compromised fetal blood supply. The eye, like other end organs, is affected by this systemic condition, but unlike in other organs, ocular media transparency allows high-resolution optical visualization of the vascular structure of the retina. Our aim was to assess how ultrasound-determined ocular blood-flow correlates with vascular structure of the retina and choriocapillaris determined by optical coherence tomography angiography (OCTA). METHODS: Plane-wave ultrasound and OCTA were performed on both eyes of 40 consecutive subjects consisting of normal controls (n = 11), mild PE (n = 5), severe PE (n = 17) and chronic or gestational hypertension (n = 7) within 72 hours following delivery. From ultrasound, we measured pulsatile flow velocity and resistance indices in the central retinal artery (CRA) and vein, the short posterior ciliary arteries (SPCAs) and choroid. From OCTA, we measured vascular density (VD) in the superficial, deep retina and choriocapillaris. We determined differences in Doppler and OCTA parameters among groups and correlations between ultrasound and OCTA. RESULTS: In severe PE, flow resistance was reduced with respect to controls. Flow velocity and resistance in the and SPCA were moderately correlated with VD in the choriocapillaris and peripapillary retina, but VD in PE did not differ significantly from controls. CONCLUSIONS: Although OCTA parameters were moderately correlated with Doppler ultrasound, OCTA did not demonstrate significant differences between PE and controls postpartum.

Maternal Morbidity Risk Factors in Nulliparas.

OBJECTIVE: For every incidence of maternal mortality, maternal morbidity is thought to occur in another 50 to 100 individuals in the United States. Multiple risk factors for severe maternal morbidity have been identified, but counseling about specific risk in pregnancy remains difficult, particularly nulliparous individuals as prior obstetric history is one of the factors influencing risk for severe maternal morbidity. The objective of this study is to examine the association between sociodemographic and laboratory assessments in the first trimester and maternal morbidity in nulliparas. STUDY DESIGN: This was a secondary analysis of a large, multicenter prospective observational cohort of nulliparas. The primary maternal outcome was a composite of hypertensive disorders of pregnancy (HDP), hemorrhage (transfusion, hemorrhage, hysterectomy, other surgery, readmission for bleeding), infection (endometritis, wound infection or dehiscence, pneumonia, sepsis, infection during labor and delivery, readmission for infection through day 14), venous thromboembolic events (VTE) (deep venous thrombosis, or pulmonary embolus), or maternal death within 14 days of delivery. Sociodemographic and clinical factors were compared between people with and without maternal morbidity. Relative risk and 95% confidence interval for maternal morbidity was calculated using log-binomial regression, adjusted for baseline characteristics that had a significant independent relationship with maternal morbidity with a p-value <0.05. RESULTS: Of 9,445 pregnant people in the analysis, 18.2% (n = 1,716) experienced the composite maternal morbidity; the most common component was HDP (13.1%, n = 1,244) followed by infection (4.43%, n = 420), hemorrhage (2.27%, n = 215), VTE (0.12%, n = 11), and death (0.01%, n = 1). In a multivariable model, self-identified Black race, first trimester obesity, pregestational diabetes, chronic hypertension, and chronic kidney disease were significantly associated with the primary maternal outcome. CONCLUSION: More than one in six nulliparas experienced the composite maternal morbidities. Maternal morbidity was associated with self-identified Black race, obesity, and multiple preexisting medical comorbidities. KEY POINTS: · One in six nulliparas experience maternal morbidity in their first pregnancy related to hypertensive disorders of pregnancy, infection, hemorrhage, and venous thromboembolism.. · Risk factors for maternal morbidity in nulliparas include Black race, prepregnancy body mass index, and preexisting medical conditions.. · The preexisting medical conditions with the strongest association with maternal morbidity included pregestational diabetes, chronic hypertension, and chronic kidney disease..