Fetal MRI findings, etiology, and outcome in prenatally diagnosed schizencephaly.

BACKGROUND AND PURPOSE: Schizencephaly is a rare brain anomaly which is increasingly detected in utero. There are limited data on the etiology and outcomes in fetal schizencephaly to guide workup and counselling. We aim to determine the associated imaging findings, etiology, and outcomes in schizencephaly detected in utero. MATERIALS AND METHODS: This retrospective cohort study included 22 fetuses with a total of 34 schizencephaly defects identified by keyword search of fetal MRI reports from 1996-2022 followed by image review. Follow-up fetal and postnatal imaging, when available, were reviewed. Data on demographics, etiology, and outcomes were extracted from the electronic medical record. RESULTS: The schizencephaly defect was open in 28/34, most common in the MCA territory (23/34), and commonly involved the frontal (16/34) lobe. Additional intracranial abnormalities were seen in all fetuses including other cortical malformations (CM, 13/22), abnormal posterior fossa (12/22), abnormal corpus callosum (10/20), and intraparenchymal hemorrhage (9/22).The cause of schizencephaly was classified as secondary (as evidenced by intraparenchymal hemorrhage at schizencephaly, monochorionic twin gestation, infection, or maternal/placental risk factor) in 64% (14/22), potentially genetic in 9% (2/22), and unknown in 27% (6/22). Among those liveborn (n=8), the following outcomes were observed: postnatal death (1/8), tube feeding (1/7), shunted hydrocephalus (1/7), epilepsy (4/7). Among those >1 year of age, cerebral palsy (4/5) and speech delay or intellectual disability (3/5) were common. CM remote from schizencephaly was associated with epilepsy (p=0.03). On postnatal imaging, open defects often involuted (8/11) and there were high rates of new/additional findings (4/6). CONCLUSIONS: In this cohort, fetal schizencephaly was always associated with additional intracranial abnormalities. In most cases, there was evidence that schizencephaly was likely secondary to prior injury. Imaging characteristics may provide clues regarding neurodevelopmental outcome. Postnatal imaging is crucial in assessing evolution as well as for detection of additional abnormalities. ABBREVIATIONS: ICH = intracranial hemorrhage; CM = cortical malformation; VM = ventriculomegaly; DGN = deep grey nuclei; SP = septum pellucidum; IPH = intraparenchymal hemorrhage; CC = corpus callosum; PMG = polymicrogyria; PVNH = periventricular nodular heterotopia; TTTS = twin-twin transfusion syndrome; GA = gestational age; CP = cerebral palsy.

Effects of Antihypertensive Therapy During Pregnancy on Postpartum Blood Pressure Control.

OBJECTIVE: To compare differences in postpartum blood pressure (BP) control (BP below 140/90 mm Hg) for participants with hypertension randomized to receive antihypertensive treatment compared with no treatment during pregnancy. METHODS: This study was a planned secondary analysis of a multicenter, open-label, randomized controlled trial (The CHAP [Chronic Hypertension and Pregnancy] trial). Pregnant participants with mild chronic hypertension (BP below 160/105 mm Hg) were randomized into two groups: active (antihypertensive treatment) or control (no treatment unless severe hypertension, BP 160/105 mm Hg or higher). Study outcomes were BP control below 140/90 mm Hg (primary) and medication nonadherence based on a composite score threshold (secondary) at the 6-week postpartum follow-up visit. Participants without follow-up BP measurements were excluded from analysis of the BP control outcome. Participants without health care professional-prescribed antihypertensives at delivery were excluded from the analysis of the adherence outcome. Multivariable logistic regression was used to adjust for potential confounders. RESULTS: Of 2,408 participants, 1,684 (864 active, 820 control) were included in the analysis. A greater percentage of participants in the active group achieved BP control (56.7% vs 51.5%; adjusted odds ratio [aOR] 1.22, 95% CI, 1.00-1.48) than in the control group. Postpartum antihypertensive prescription was higher in the active group (81.7% vs 58.4%, P<.001), and nonadherence did not differ significantly between groups (aOR 0.81, 95% CI, 0.64-1.03). CONCLUSION: Antihypertensive treatment of mild chronic hypertension during pregnancy was associated with better BP control below 140/90 mm Hg in the immediate postpartum period.

Blood Pressure Control in Pregnant Patients with Chronic Hypertension and Diabetes: Should <130/80 be the Target?

BACKGROUND: The Chronic Hypertension and Pregnancy Study (CHAP) demonstrated that a target blood pressure of <140/90 mm Hg during pregnancy is associated with improved perinatal outcomes. Outside of pregnancy, pharmacologic therapy for patients with diabetes and hypertension is adjusted to a target blood pressure of <130/80 mm Hg. During pregnancy, patients with both diabetes and chronic hypertension may also benefit from tighter control with a target blood pressure (BP) <130/80 mm Hg. OBJECTIVE: We compared perinatal outcomes in patients with hypertension and diabetes who achieved BP <130/80 versus 130-139/80-89 mm Hg. STUDY DESIGN: This was a secondary analysis of a multi-center randomized controlled trial. Participants were included in this secondary analysis if they had diabetes diagnosed prior to pregnancy or at <20 weeks' gestation and at least two recorded BP measurements prior to delivery. Average systolic and diastolic BP were calculated using ambulatory antenatal BPs. The primary composite outcome was preeclampsia with severe features, indicated preterm birth <35 weeks, or placental abruption. Secondary outcomes were components of the primary outcome, cesarean delivery, fetal or neonatal death, neonatal intensive care unit (NICU) admission, and small for gestational age (SGA). Comparisons were made between those with an average systolic BP <130 mm Hg and average diastolic BP <80 mm Hg and those with an average systolic blood pressure 130-139 mm Hg or diastolic blood pressure 80-89 mm Hg using Student's t-test and chi-squared tests. Multivariable log-binomial regression models were used to evaluate risk ratios between blood pressure groups for dichotomous outcomes while accounting for baseline covariates. RESULTS: Of 434 participants included, 150 (34.6%) had an average blood pressure less than 130/80 mm Hg. Participants with an average blood pressure less than 130/80 were more likely to be on antihypertensive medications at the start of pregnancy and more likely to have newly diagnosed DM prior to 20 weeks. Participants with an average blood pressure less than 130/80 mm Hg were less likely to have the primary adverse perinatal outcome (19.3% vs 46.5%, adjusted relative risk (aRR) 0.43, 95% CI 0.30-0.61, p<0.01), with decreased risks specifically of preeclampsia with severe features (aRR 0.35, 95% CI 0.23-0.54) and indicated preterm birth prior to 35 weeks (aRR 0.44, 95% CI 0.24-0.79). The risk of NICU admission was lower in the lower blood pressure group (aRR 0.74, 95% CI 0.59-0.94). No differences were noted in cesarean delivery (aRR 1.04, 95% CI 0.90-1.20), fetal or neonatal death (aRR 0.59, 95% CI 0.12-2.92). SGA less than the 10th percentile was lower in the lower blood pressure group (aRR 0.37, 95% CI 0.14-0.96). CONCLUSION: In those with chronic hypertension and diabetes prior to 20 weeks, achieving an average goal blood pressure of <130/80 mm Hg may be associated with improved perinatal outcomes.

Fetal Intraparenchymal Hemorrhage Imaging Patterns, Etiology, and Outcomes: A Single Center Cohort Study.

OBJECTIVE: This study examines associations among fetal brain magnetic resonance imaging (MRI) injury patterns, etiologies, and outcomes in fetal intraparenchymal hemorrhage (IPH). METHODS: This is a retrospective, single-center cohort study of IPH diagnosed on fetal MRI (1996-2022). IPH and associated abnormalities were categorized by 2 pediatric neuroradiologists; electronic medical records were reviewed by 2 pediatric neurologists to classify etiology and outcomes including cerebral palsy, epilepsy, developmental delay, and death. RESULTS: Forty-four fetuses with IPH were identified (34 singleton and 10 twin gestations) with MRI at median 24 weeks gestation (interquartile range [IQR] = 22-28 weeks). IPH was commonly supratentorial (84%) and focal (50%) or focal with diffuse injury (43%) and was often associated with germinal matrix hemorrhage (GMH; 75%) and/or intraventricular hemorrhage (IVH; 52%). An etiology was identified in 75%, including twin-twin transfusion syndrome (TTTS, n = 10), COL4A1/2 variants (n = 8), or other fetal/maternal conditions (n = 15). COL4A1/2 variants were associated with focal IPH and the presence of hemorrhagic porencephaly, and intrauterine transfusion was associated with infratentorial hemorrhage. Twenty-two fetuses were liveborn, and 18 pregnancies were terminated. Among those with follow-up ≥ 12 months (median = 7 years), 12 of 13 had cerebral palsy, 6 of 13 had developmental delay, and 5 of 13 had epilepsy. INTERPRETATION: An etiology for fetal IPH with or without GMH-IVH is identified in most cases in our cohort and is commonly TTTS, COL4A1/2 variants, or other maternal/fetal comorbidities. Pattern of fetal IPH on MRI is associated with etiology. Cerebral palsy and neurodevelopmental impairment were common in liveborn infants. Genetic studies should be considered in cases of fetal IPH without an otherwise apparent cause. ANN NEUROL 2024.

Nipocalimab in Early-Onset Severe Hemolytic Disease of the Fetus and Newborn.

BACKGROUND: In early-onset severe hemolytic disease of the fetus and newborn (HDFN), transplacental transfer of maternal antierythrocyte IgG alloantibodies causes fetal anemia that leads to the use of high-risk intrauterine transfusions in order to avoid fetal hydrops and fetal death. Nipocalimab, an anti-neonatal Fc receptor blocker, inhibits transplacental IgG transfer and lowers maternal IgG levels. METHODS: In an international, open-label, single-group, phase 2 study, we assessed treatment with intravenous nipocalimab (30 or 45 mg per kilogram of body weight per week) administered from 14 to 35 weeks' gestation in participants with pregnancies at high risk for recurrent early-onset severe HDFN. The primary end point was live birth at 32 weeks' gestation or later without intrauterine transfusions as assessed against a historical benchmark (0%; clinically meaningful difference, 10%). RESULTS: Live birth at 32 weeks' gestation or later without intrauterine transfusions occurred in 7 of 13 pregnancies (54%; 95% confidence interval, 25 to 81) in the study. No cases of fetal hydrops occurred, and 6 participants (46%) did not receive any antenatal or neonatal transfusions. Six fetuses received an intrauterine transfusion: five fetuses at 24 weeks' gestation or later and one fetus before fetal loss at 22 weeks and 5 days' gestation. Live birth occurred in 12 pregnancies. The median gestational age at delivery was 36 weeks and 4 days. Of the 12 live-born infants, 1 received one exchange transfusion and one simple transfusion and 5 received only simple transfusions. Treatment-related decreases in the alloantibody titer and IgG level were observed in maternal samples and cord blood. No unusual maternal or pediatric infections were observed. Serious adverse events were consistent with HDFN, pregnancy, or prematurity. CONCLUSIONS: Nipocalimab treatment delayed or prevented fetal anemia or intrauterine transfusions, as compared with the historical benchmark, in pregnancies at high risk for early-onset severe HDFN. (Funded by Janssen Research and Development; UNITY ClinicalTrials.gov number, NCT03842189.).

Pregnancy Outcomes of Nifedipine Compared With Labetalol for Oral Treatment of Mild Chronic Hypertension.

OBJECTIVE: To evaluate maternal and neonatal outcomes by type of antihypertensive used in participants of the CHAP (Chronic Hypertension in Pregnancy) trial. METHODS: We conducted a planned secondary analysis of CHAP, an open-label, multicenter, randomized trial of antihypertensive treatment compared with standard care (no treatment unless severe hypertension developed) in pregnant patients with mild chronic hypertension (blood pressure 140-159/90-104 mm Hg before 20 weeks of gestation) and singleton pregnancies. We performed three comparisons based on medications prescribed at enrollment: labetalol compared with standard care, nifedipine compared with standard care, and labetalol compared with nifedipine. Although active compared with standard care groups were randomized, medication assignment within the active treatment group was not random but based on clinician or patient preference. The primary outcome was the occurrence of superimposed preeclampsia with severe features, preterm birth before 35 weeks of gestation, placental abruption, or fetal or neonatal death. The key secondary outcome was small for gestational age (SGA) neonates. We also compared medication adverse effects between groups. Relative risks (RRs) and 95% CIs were estimated with log binomial regression to adjust for confounding. RESULTS: Of 2,292 participants analyzed, 720 (31.4%) received labetalol, 417 (18.2%) received nifedipine, and 1,155 (50.4%) received no treatment. The mean gestational age at enrollment was 10.5±3.7 weeks; nearly half of participants (47.5%) identified as non-Hispanic Black; and 44.5% used aspirin. The primary outcome occurred in 217 (30.1%), 130 (31.2%), and 427 (37.0%) in the labetalol, nifedipine, and standard care groups, respectively. Risk of the primary outcome was lower among those receiving treatment (labetalol use vs standard adjusted RR 0.82, 95% CI, 0.72-0.94; nifedipine use vs standard adjusted RR 0.84, 95% CI, 0.71-0.99), but there was no significant difference in risk when labetalol was compared with nifedipine (adjusted RR 0.98, 95% CI, 0.82-1.18). There were no significant differences in SGA or serious adverse events between participants receiving labetalol and those receiving nifedipine. CONCLUSION: No significant differences in predetermined maternal or neonatal outcomes were detected on the basis of the use of labetalol or nifedipine for treatment of chronic hypertension in pregnancy. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT02299414.

Optimal Timing of Delivery for Pregnant Individuals With Mild Chronic Hypertension.

OBJECTIVE: To investigate the optimal gestational age to deliver pregnant people with chronic hypertension to improve perinatal outcomes. METHODS: We conducted a planned secondary analysis of a randomized controlled trial of chronic hypertension treatment to different blood pressure goals. Participants with term, singleton gestations were included. Those with fetal anomalies and those with a diagnosis of preeclampsia before 37 weeks of gestation were excluded. The primary maternal composite outcome included death, serious morbidity (heart failure, stroke, encephalopathy, myocardial infarction, pulmonary edema, intensive care unit admission, intubation, renal failure), preeclampsia with severe features, hemorrhage requiring blood transfusion, or abruption. The primary neonatal outcome included fetal or neonatal death, respiratory support beyond oxygen mask, Apgar score less than 3 at 5 minutes, neonatal seizures, or suspected sepsis. Secondary outcomes included intrapartum cesarean birth, length of stay, neonatal intensive care unit admission, respiratory distress syndrome (RDS), transient tachypnea of the newborn, and hypoglycemia. Those with a planned delivery were compared with those expectantly managed at each gestational week. Adjusted odds ratios (aORs) with 95% CIs are reported. RESULTS: We included 1,417 participants with mild chronic hypertension; 305 (21.5%) with a new diagnosis in pregnancy and 1,112 (78.5%) with known preexisting hypertension. Groups differed by body mass index (BMI) and preexisting diabetes. In adjusted models, there was no association between planned delivery and the primary maternal or neonatal composite outcome in any gestational age week compared with expectant management. Planned delivery at 37 weeks of gestation was associated with RDS (7.9% vs 3.0%, aOR 2.70, 95% CI, 1.40-5.22), and planned delivery at 37 and 38 weeks was associated with neonatal hypoglycemia (19.4% vs 10.7%, aOR 1.97, 95% CI, 1.27-3.08 in week 37; 14.4% vs 7.7%, aOR 1.82, 95% CI, 1.06-3.10 in week 38). CONCLUSION: Planned delivery in the early-term period compared with expectant management was not associated with a reduction in adverse maternal outcomes. However, it was associated with increased odds of some neonatal complications. Delivery timing for individuals with mild chronic hypertension should weigh maternal and neonatal outcomes in each gestational week but may be optimized by delivery at 39 weeks.

Mean Arterial Pressure and Neonatal Outcomes in Pregnancies Complicated by Mild Chronic Hypertension.

OBJECTIVE: To estimate the association between mean arterial pressure during pregnancy and neonatal outcomes in participants with chronic hypertension using data from the CHAP (Chronic Hypertension and Pregnancy) trial. METHODS: A secondary analysis of the CHAP trial, an open-label, multicenter randomized trial of antihypertensive treatment in pregnancy, was conducted. The CHAP trial enrolled participants with mild chronic hypertension (blood pressure [BP] 140-159/90-104 mm Hg) and singleton pregnancies less than 23 weeks of gestation, randomizing them to active treatment (maintained on antihypertensive therapy with a goal BP below 140/90 mm Hg) or standard treatment (control; antihypertensives withheld unless BP reached 160 mm Hg systolic BP or higher or 105 mm Hg diastolic BP or higher). We used logistic regression to measure the strength of association between mean arterial pressure (average and highest across study visits) and to select neonatal outcomes. Unadjusted and adjusted odds ratios (per 1-unit increase in millimeters of mercury) of the primary neonatal composite outcome (bronchopulmonary dysplasia, retinopathy of prematurity, necrotizing enterocolitis, or intraventricular hemorrhage grade 3 or 4) and individual secondary outcomes (neonatal intensive care unit admission [NICU], low birth weight [LBW] below 2,500 g, and small for gestational age [SGA]) were calculated. RESULTS: A total of 2,284 participants were included: 1,155 active and 1,129 control. Adjusted models controlling for randomization group demonstrated that increasing average mean arterial pressure per millimeter of mercury was associated with an increase in each neonatal outcome examined except NEC, specifically neonatal composite (adjusted odds ratio [aOR] 1.12, 95% CI, 1.09-1.16), NICU admission (aOR 1.07, 95% CI, 1.06-1.08), LBW (aOR 1.12, 95% CI, 1.11-1.14), SGA below the fifth percentile (aOR 1.03, 95% CI, 1.01-1.06), and SGA below the 10th percentile (aOR 1.02, 95% CI, 1.01-1.04). Models using the highest mean arterial pressure as opposed to average mean arterial pressure also demonstrated consistent associations. CONCLUSION: Increasing mean arterial pressure was positively associated with most adverse neonatal outcomes except NEC. Given that the relationship between mean arterial pressure and adverse pregnancy outcomes may not be consistent at all mean arterial pressure levels, future work should attempt to further elucidate whether there is an absolute threshold or relative change in mean arterial pressure at which fetal benefits are optimized along with maternal benefits. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov , NCT02299414.

Trends in Reporting of Nuchal Translucency Measurements After the Clinical Introduction of Cell-Free DNA Screening.

Nuchal translucency (NT) measurement in conjunction with serum analytes has been used for first-trimester aneuploidy screening in the United States since 2005. We sought to analyze the trends in reporting of NT measurements to the Nuchal Translucency Quality Review program in all pregnancies beginning after the clinical introduction of cell-free DNA (cfDNA) screening for fetal aneuploidy in 2011. Overall, reported NT measurements decreased 74.3% from 2012 to 2022. A similar decline was noted among individuals with pregnancies at increased risk for aneuploidy based on patient age and twin gestations. The decrease in reporting aligns temporally with the availability of cfDNA screening and the coronavirus disease 2019 (COVID-19) pandemic.

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.

Genetic ancestry and diagnostic yield of exome sequencing in a diverse population.

It has been suggested that diagnostic yield (DY) from Exome Sequencing (ES) may be lower among patients with non-European ancestries than those with European ancestry. We examined the association of DY with estimated continental/subcontinental genetic ancestry in a racially/ethnically diverse pediatric and prenatal clinical cohort. Cases (N = 845) with suspected genetic disorders underwent ES for diagnosis. Continental/subcontinental genetic ancestry proportions were estimated from the ES data. We compared the distribution of genetic ancestries in positive, negative, and inconclusive cases by Kolmogorov-Smirnov tests and linear associations of ancestry with DY by Cochran-Armitage trend tests. We observed no reduction in overall DY associated with any genetic ancestry (African, Native American, East Asian, European, Middle Eastern, South Asian). However, we observed a relative increase in proportion of autosomal recessive homozygous inheritance versus other inheritance patterns associated with Middle Eastern and South Asian ancestry, due to consanguinity. In this empirical study of ES for undiagnosed pediatric and prenatal genetic conditions, genetic ancestry was not associated with the likelihood of a positive diagnosis, supporting the equitable use of ES in diagnosis of previously undiagnosed but potentially Mendelian disorders across all ancestral populations.

Prenatal vs postnatal diagnosis of 22q11.2 deletion syndrome: cardiac and noncardiac outcomes through 1 year of age.

BACKGROUND: The 22q11.2 deletion syndrome is the most common microdeletion syndrome and is frequently associated with congenital heart disease. Prenatal diagnosis of 22q11.2 deletion syndrome is increasingly offered. It is unknown whether there is a clinical benefit to prenatal detection as compared with postnatal diagnosis. OBJECTIVE: This study aimed to determine differences in perinatal and infant outcomes between patients with prenatal and postnatal diagnosis of 22q11.2 deletion syndrome. STUDY DESIGN: This was a retrospective cohort study across multiple international centers (30 sites, 4 continents) from 2006 to 2019. Participants were fetuses, neonates, or infants with a genetic diagnosis of 22q11.2 deletion syndrome by 1 year of age with or without congenital heart disease; those with prenatal diagnosis or suspicion (suggestive ultrasound findings and/or high-risk cell-free fetal DNA screen for 22q11.2 deletion syndrome with postnatal confirmation) were compared with those with postnatal diagnosis. Perinatal management, cardiac and noncardiac morbidity, and mortality by 1 year were assessed. Outcomes were adjusted for presence of critical congenital heart disease, gestational age at birth, and site. RESULTS: A total of 625 fetuses, neonates, or infants with 22q11.2 deletion syndrome (53.4% male) were included: 259 fetuses were prenatally diagnosed (156 [60.2%] were live-born) and 122 neonates were prenatally suspected with postnatal confirmation, whereas 244 infants were postnatally diagnosed. In the live-born cohort (n=522), 1-year mortality was 5.9%, which did not differ between groups but differed by the presence of critical congenital heart disease (hazard ratio, 4.18; 95% confidence interval, 1.56-11.18; P<.001) and gestational age at birth (hazard ratio, 0.78 per week; 95% confidence interval, 0.69-0.89; P<.001). Adjusting for critical congenital heart disease and gestational age at birth, the prenatal cohort was less likely to deliver at a local community hospital (5.1% vs 38.2%; odds ratio, 0.11; 95% confidence interval, 0.06-0.23; P<.001), experience neonatal cardiac decompensation (1.3% vs 5.0%; odds ratio, 0.11; 95% confidence interval, 0.03-0.49; P=.004), or have failure to thrive by 1 year (43.4% vs 50.3%; odds ratio, 0.58; 95% confidence interval, 0.36-0.91; P=.019). CONCLUSION: Prenatal detection of 22q11.2 deletion syndrome was associated with improved delivery management and less cardiac and noncardiac morbidity, but not mortality, compared with postnatal detection.

The utility of gene sequencing in identifying an underlying genetic disorder in prenatally suspected lower urinary tract obstruction.

OBJECTIVE: Fetal megacystis generally presents as suspected lower urinary tract obstruction (LUTO), which is associated with severe perinatal morbidity. Genetic etiologies underlying LUTO or a LUTO-like initial presentation are poorly understood. Our objectives are to describe single gene etiologies in fetuses initially ascertained to have suspected LUTO and to elucidate genotype-phenotype correlations. METHODS: A retrospective case series of suspected fetal LUTO positive for a molecular diagnosis was collected from five centers in the Fetal Sequencing Consortium. Demographics, sonograms, genetic testing including variant classification, and delivery outcomes were abstracted. RESULTS: Seven cases of initially prenatally suspected LUTO-positive for a molecular diagnosis were identified. In no case was the final diagnosis established as urethral obstruction that is, LUTO. All variants were classified as likely pathogenic or pathogenic. Smooth muscle deficiencies involving the bladder wall and interfering with bladder emptying were identified in five cases: MYOCD (2), ACTG2 (2), and MYH11 (1). Other genitourinary and/or non-genitourinary malformations were seen in two cases involving KMT2D (1) and BBS10 (1). CONCLUSION: Our series illustrates the value of molecular diagnostics in the workup of fetuses who present with prenatally suspected LUTO but who may have a non-LUTO explanation for their prenatal ultrasound findings.

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.

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.