Maternal-fetal comorbidities and obstetrical outcomes of fetal single ventricle cardiac defects: 10 years' experience with a multidisciplinary management protocol at a single center.

OBJECTIVES: To describe and compare maternal and fetal comorbidities and obstetrical outcomes in pregnancies with hypoplastic left and right heart (HLHS and HRH) single ventricle cardiac defects (SVCD) from a single center under a multidisciplinary protocol. METHOD: A single center retrospective review of fetal SVCD from 2013 to 2022. Maternal-fetal comorbidities, delivery, and postnatal outcomes were compared between HLHS and HRH using descriptive statistics and univariate and multivariate analyses. RESULTS: Of 181 SVCD pregnancies (131 HLHS; 50 HRH), 9% underwent termination, 4% elected comfort care, 5 died in utero and 147/152 liveborns survived to the first cardiac intervention. Cesarean delivery occurred in 57 cases (37%), planned in 36 and unplanned in 21. Comorbidities, which did not differ between HLHS and HRH, included fetal growth restriction (FGR, 17%), prematurity (14%), maternal hypertension (9%), maternal obesity (50%), fetal extracardiac anomalies and chromosome anomalies (12%, 13%). In multivariate analysis, only earlier gestational age at delivery and oligohydramnios predicted decreased odds of survival at one year. CONCLUSION: Maternal-fetal comorbidities are common in both HLHS and HRH. Earlier gestational age at delivery and oligohydramnios predict lower postnatal survival. FGR, even with severe early onset, did not significantly impact short- or long-term neonatal survival in single ventricle conditions.

Successful antenatal treatment of MAGED2-related Bartter syndrome and review of treatment options and efficacy.

A new form of transient antenatal Bartter syndrome (aBS) was recently identified that is associated with the X-linked MAGED2 variant. Case reports demonstrate that this variant leads to severe polyhydramnios that may result in preterm birth or pregnancy loss. There is limited but promising evidence that amnioreductions may improve fetal outcomes in this rare condition. We report a woman with two affected pregnancies. In the first pregnancy, the patient was diagnosed with mild-to-moderate polyhydramnios in the second trimester that ultimately resulted in preterm labor and delivery at 25 weeks with fetal demise. Whole exome sequencing of the amniotic fluid sample resulted after the pregnancy loss and revealed a c.1337G>A MAGED2 variant that was considered diagnostically. The subsequent pregnancy was confirmed by chorionic villi sampling to also be affected by this variant. The pregnancy was managed with frequent ultrasounds and three amnioreductions that resulted in spontaneous vaginal delivery at 37 weeks and 6 days of a viable newborn with no evidence of overt electrolyte abnormalities suggesting complete resolution. A detailed review of the published cases of MAGED2-related transient aBS is provided. Our review focuses on individuals who received antenatal treatment. A total of 31 unique cases of MAGED2-related transient aBS were compiled. Amnioreduction was performed in 23 cases and in 18 cases no amnioreduction was performed. The average gestational age at delivery was significantly lower in cases without serial amnioreduction (28.7 vs. 30.71 weeks, p = 0.03). Neonatal mortality was seen in 5/18 cases without serial amnioreduction, and no mortality was observed in the cases with serial amnioreduction. In cases of second trimester severe polyhydramnios without identifiable cause, whole exome sequencing should be considered. Intensive ultrasound surveillance and serial amnioreduction is recommended for the management of MAGED2-related transient aBS.

North American Fetal Therapy Network: Maternal Outcomes in Fetal Aqueductal Stenosis.

INTRODUCTION: Fetal aqueductal stenosis (AS) affects approximately 1:1,000 pregnancies. Obstruction of cerebral spinal fluid circulation occurs at the aqueduct of Sylvius, leading to progressive hydrocephalus and macrocephaly, which often necessitates cesarean section (CS). The purpose of this study was to describe maternal outcomes associated with fetal AS. METHODS: This study is conducted through the North American Fetal Therapy Network (NAFTNet). Subjects with a prenatal diagnosis of severe fetal central nervous system ventriculomegaly were recruited and followed longitudinally. Maternal events around the delivery of fetuses with AS were recorded and analyzed. RESULTS: Thirty-seven subjects with fetal AS confirmed by neonatal neuroimaging were analyzed. The average gestational age at delivery was 36.7 weeks. Overall, 86% were delivered by CS, and 62% of these were elective. Ninety-one percent of CSs were performed through a Pfannenstiel abdominal incision. A classical uterine incision was required in 13% of cesarean deliveries. The peripartum complication rate was 27%. CONCLUSION: Women carrying a fetus with AS were at risk for preterm birth, cesarean delivery, a classical uterine incision, and peripartum complications. These data highlight the maternal morbidity associated with fetal AS and the potential benefit of in utero therapy not only for neonatal outcomes but also for maternal outcomes.

Prenatal Diagnosis of Fetal Aqueductal Stenosis: A Multicenter Prospective Observational Study through the North American Fetal Therapy Network.

INTRODUCTION: A critical component of an evidence-based reassessment of in-utero intervention for fetal aqueductal stenosis (fetal AS) is determining if the prenatal diagnosis can be accurately made at a gestational age amenable to in-utero intervention. METHODS: A multicenter, prospective, observational study was conducted through the North American Fetal Therapy Network (NAFTNet). Pregnancies complicated by severe central nervous system (CNS) ventriculomegaly (lateral ventricle diameter >15 mm) not secondary to a primary diagnosis (myelomeningocele, encephalocele, etc.) were recruited at diagnosis. Imaging and laboratory findings were recorded in an online REDCap database. After evaluation, investigators were asked to render their degree of confidence in the diagnosis of fetal AS. The prenatal diagnosis was compared to the postnatal diagnosis obtained through neonatal neuroimaging. Performance characteristics of ultrasound and magnetic resonance imaging (MRI) were calculated, as was the mean gestational age at diagnosis. RESULTS: Between April 2015 and October 2022, eleven NAFTNet centers contributed 64 subjects with severe fetal CNS ventriculomegaly. Of these, 56 had both prenatal and postnatal diagnoses recorded. Ultrasound revealed 32 fetal AS true positives, 4 false positives, 7 false negatives, and 13 true negatives, rendering a sensitivity of 0.82, a specificity of 0.76, a positive predictive value of 0.89, and a negative predictive value of 0.65. The mean gestational age at diagnosis by ultrasound was 25.5 weeks (std +/- 4.7 weeks). The proportion of agreement (true positive + true negative/n) was highest at 24 weeks gestation. For fetal MRI (n = 35), the sensitivity for fetal AS was 0.95, specificity was 0.69, positive predictive value was 0.84, and negative predictive value was 0.90. MRI was performed at 25 weeks on average. CONCLUSION: The prenatal diagnosis of fetal AS can be made with accuracy at a gestational age potentially amenable to in-utero intervention. Only 7% of subjects were incorrectly diagnosed prenatally with fetal AS by ultrasound and 11% by MRI. Diagnostic accuracy of fetal AS will likely improve with increased experience.

Fetal lung volumes measured by MRI predict pulmonary morbidity among infants with giant omphaloceles.

OBJECTIVE: Giant omphaloceles (GO) have associated pulmonary hypoplasia and respiratory complications. Total lung volumes (TLV) on fetal MRI can prognosticate congenital diaphragmatic hernia outcomes; however, its applicability to GO is unknown. We hypothesize that late gestation TLV and observed-to-expected TLV (O/E TLV) on fetal MRI correlate with postnatal pulmonary morbidity in GO. METHOD: A single-institution retrospective review of GO evaluated between 2012 and 2022 was performed. Fetal MRI TLV between 32 and 36 weeks' gestation and O/E TLV throughout gestation were calculated and correlated with postnatal outcomes. RESULTS: 86 fetuses with omphaloceles were evaluated; however, only 26 met strict inclusion criteria. MRIs occurred between 18 and 36 weeks' gestation. Those requiring delivery room intubation had significantly lower late gestation TLV and O/E TLV. O/E TLV predicted tracheostomy placement and survival. Neither TLV nor O/E TLV predicted the length of hospitalization or supplemental oxygen after discharge. Three fetuses had a TLV less than 35 mL: one died of respiratory failure, and the other two required tracheostomy. CONCLUSIONS: Fetal MRI TLV measured between 32 and 36 weeks' gestation and O/E TLV predict the need for delivery room intubation and tracheostomy. O/E TLV correlated with survival. These data support fetal MRI as a prognostic tool to predict GO associated pulmonary morbidity.

Umbilical Venous Volume Flow in Late-Onset Fetal Growth Restriction.

OBJECTIVES: Umbilical vein flow (UVF) is reduced in fetal growth restriction (FGR). We compared absolute and size-adjusted UVF (estimated fetal weight [EFW] and abdominal circumference [AC]) and rates of abnormal UVF parameters (<10th percentile) among FGR fetuses meeting Delphi criteria (FGR-D) against small for gestational age (SGA) fetuses and appropriate for gestational age (AGA) controls. METHODS: Absolute UVF, UVF/EFW, and UVF/AC were compared between 73 FGR pregnancies (35 FGR-D, 38 SGA) and 108 AGA controls. Rates of abnormal UVF were compared to abnormal umbilical artery pulsatility index (UAPI). Independent samples t-tests, Mann-Whitney U, odds ratio (OR), chi-squared, and Fisher's exact tests were used as appropriate. RESULTS: Mean absolute UVF was significantly decreased in FGR-D compared to AGA (P = .0147), but not between SGA and AGA fetuses. The incidence of both abnormal absolute UVF and UVF/AC values (<10th centile) was higher among late-onset FGR fetuses versus AGA fetuses (UVF: OR 2.7, confidence interval [CI] 1.37-5.4; UVF/AC: OR 2.73, CI 1.37-5.4). UVF was more frequently abnormal than UAPI and in only two fetuses were both Doppler values abnormal. CONCLUSION: Absolute UVF is altered in late-onset FGR, and most pronounced among FGR-D. UVF may provide additional insight into fetal compromise in those affected by growth restriction.

Doppler velocimetry discordance between paired umbilical artery vessels and clinical implications in fetal growth restriction.

BACKGROUND: Studies revealing a discrepancy in umbilical artery Dopplers between the two umbilical arteries in normally-grown fetuses necessitates further evaluation of the paired umbilical arteries in the setting of fetal growth restriction as this is a critical component in the surveillance of this population. OBJECTIVE: Umbilical artery Doppler sampling in fetal growth restriction is typically assessed in 1 umbilical artery in a free loop of cord. Although discrepancies of >20% between the 2 umbilical arteries occur in 1 of 3 normal pregnancies, this has not been assessed in fetal growth restriction. Our objectives were to determine the frequency of discordant Doppler pulsatility indices between paired umbilical arteries in a fetal growth restriction cohort and to determine if sampling of 1 or both arteries alters surveillance or timing of delivery. STUDY DESIGN: A cohort of 425 growth-restricted fetuses between 25 and 39 weeks of gestation had umbilical artery Doppler pulsatility indices determined from both umbilical arteries in a midsegment of the cord to determine: (1) the discrepancy percentage between paired umbilical artery pulsatility indices and (2) the frequency of both arteries being normal, abnormal, or discordant (pulsatility index < and >95th percentile). To determine what sampling method increased the detection of an abnormal Doppler index, 3 sampling methods were compared: (1) average pulsatility index from both umbilical arteries, (2) pulsatility index from 1 umbilical artery chosen randomly, and (3) highest pulsatility index of the 2 umbilical arteries. RESULTS: The mean percentage difference between umbilical artery pulsatility indices was 11.7%, and in 15.8% of cases, it exceeded 20%. Both umbilical artery pulsatility indices were normal in 71.1% (302/425), abnormal in 12.2% (52/425), and discordant in 16.7% (71/425) of cases (P<.0001). Of the 3 sampling methods, the pulsatility index was abnormal in: (1) 19.2% (82/425) of cases when averaged from both umbilical arteries, (2) 22.1% (94/425) of cases when choosing 1 umbilical artery at random, and (3) 28.9% (123/425) of cases when the highest umbilical artery pulsatility index was used (P=.003). CONCLUSION: In this large fetal growth restriction cohort, the overall discrepancy between the 2 umbilical artery pulsatility indices was 11.7%. Among fetuses with at least 1 abnormal umbilical artery pulsatility index, 71 of 123 (57.7%) had 1 normal pulsatility index and 1 abnormal. Thus, the number of arteries sampled and the sampling method used may alter clinical decision-making, including frequency of surveillance and timing of delivery.

The role of the fetal biophysical profile in the management of fetal growth restriction.

Growth-restricted fetuses are at risk of hypoxemia, acidemia, and stillbirth because of progressive placental dysfunction. Current fetal well-being, neonatal risks following delivery, and the anticipated rate of fetal deterioration are the major management considerations in fetal growth restriction. Surveillance has to quantify the fetal risks accurately to determine the delivery threshold and identify the testing frequency most likely to capture future deterioration and prevent stillbirth. From the second trimester onward, the biophysical profile score correlates over 90% with the current fetal pH, and a normal score predicts a pH >7.25 with a 100% positive predictive value; an abnormal score on the other hand predicts current fetal acidemia with similar certainty. Between 30% and 70% of growth-restricted fetuses with a nonreactive heart rate require biophysical profile scoring to verify fetal well-being, and an abnormal score in 8% to 27% identifies the need for delivery, which is not suspected by Doppler findings. Future fetal well-being is not predicted by the biophysical profile score, which emphasizes the importance of umbilical artery Doppler and amniotic fluid volume to determine surveillance frequency. Studies with integrated surveillance strategies that combine frequent heart rate monitoring with biophysical profile scoring and Doppler report better outcomes and stillbirth rates of between 0% and 4%, compared with those between 8% and 11% with empirically determined surveillance frequency. The variations in clinical behavior and management challenges across gestational age are better addressed when biophysical profile scoring is integrated into the surveillance of fetal growth restriction. This review aims to provide guidance on biophysical profile scoring in the in- and outpatient management of fetal growth restriction.

Clinical Opinion: The diagnosis and management of suspected fetal growth restriction: an evidence-based approach.

This study reviewed the literature about the diagnosis, antepartum surveillance, and time of delivery of fetuses suspected to be small for gestational age or growth restricted. Several guidelines have been issued by major professional organizations, including the International Society of Ultrasound in Obstetrics and Gynecology and the Society for Maternal-Fetal Medicine. The differences in recommendations, in particular about Doppler velocimetry of the ductus venosus and middle cerebral artery, have created confusion among clinicians, and this review has intended to clarify and highlight the available evidence that is pertinent to clinical management. A fetus who is small for gestational age is frequently defined as one with an estimated fetal weight of <10th percentile. This condition has been considered syndromic and has been frequently attributed to fetal growth restriction, a constitutionally small fetus, congenital infections, chromosomal abnormalities, or genetic conditions. Small for gestational age is not synonymous with fetal growth restriction, which is defined by deceleration of fetal growth determined by a change in fetal growth velocity. An abnormal umbilical artery Doppler pulsatility index reflects an increased impedance to flow in the umbilical circulation and is considered to be an indicator of placental disease. The combined finding of an estimated fetal weight of <10th percentile and abnormal umbilical artery Doppler velocimetry has been widely accepted as indicative of fetal growth restriction. Clinical studies have shown that the gestational age at diagnosis can be used to subclassify suspected fetal growth restriction into early and late, depending on whether the condition is diagnosed before or after 32 weeks of gestation. The early type is associated with umbilical artery Doppler abnormalities, whereas the late type is often associated with a low pulsatility index in the middle cerebral artery. A large randomized clinical trial indicated that in the context of early suspected fetal growth restriction, the combination of computerized cardiotocography and fetal ductus venosus Doppler improves outcomes, such that 95% of surviving infants have a normal neurodevelopmental outcome at 2 years of age. A low middle cerebral artery pulsatility index is associated with an adverse perinatal outcome in late fetal growth restriction; however, there is no evidence supporting its use to determine the time of delivery. Nonetheless, an abnormality in middle cerebral artery Doppler could be valuable to increase the surveillance of the fetus at risk. We propose that fetal size, growth rate, uteroplacental Doppler indices, cardiotocography, and maternal conditions (ie, hypertension) according to gestational age are important factors in optimizing the outcome of suspected fetal growth restriction.

3D Fractional Limb Volume Identifies Reduced Subcutaneous and Lean Mass in Fetal Growth Restriction.

OBJECTIVES: Fetal 2D and 3D fractional limb volume (FLV) measurements by ultrasound can detect fetal lean and subcutaneous mass and possibly percent body fat. Our objectives were to 1) compare FLV measurements in fetuses with fetal growth restriction (FGR) versus small for gestational age (SGA) defined by the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG)-supported international Delphi consensus and 2) correlate FLV findings with birth metrics. We hypothesize that FLV measurements will be significantly smaller in FGR versus SGA fetuses and will correlate closer with Ponderal index (PIx) in the neonate than abdominal circumference (AC). METHODS: Patients were categorized as FGR or SGA as defined by ISUOG. Total thigh volume (TTV), volumes of lean mass (LMV), and fat mass volume (FMV) were calculated from 3D acquisitions. Measurements were compared between groups and correlated with birthweight (BW) and PIx (BW/crown-heal length). RESULTS: The FGR group (n = 37) delivered earlier (37/2 versus 38/0; P = .0847), were lighter (2.2 kg versus 2.6 kg; P = .0003) and had lower PIx (0.023 versus 0.025; P = .0013) than SGAs (n = 22). FGRs had reduced TTV (40.6 versus 48.4 cm3 ; P = .0164), FMV (20.8 versus 25.3 cm3 ; P = .0413), and LMV (19.8 versus 23.1 cm3 ; P = .0387). AC had the highest area under the curve (0.69) for FGR. FMV was more strongly associated with PIx than the AC (P = .0032). CONCLUSIONS: The AC and FLV measurements were significantly reduced in FGR fetuses compared to SGAs. While the AC outperformed FLV in predicting FGR, the FLV correlated best with PIx, which holds investigative promise.

Amniotic fluid microRNA profiles in twin-twin transfusion syndrome with and without severe recipient cardiomyopathy.

BACKGROUND: Twin-twin transfusion syndrome presents many challenges for clinicians, and the optimal means of identifying pregnancies that will benefit most from intervention is controversial. There is currently no clinically available biomarker to detect twin-twin transfusion syndrome or to stratify cases based on the risk factors. microRNAs are small RNAs that regulate gene expression and are biomarkers for various disease processes, including adult and pediatric heart failure. To date, no studies have investigated amniotic fluid microRNAs as biomarkers for disease severity, specifically for severe recipient cardiomyopathy in twin-twin transfusion syndrome cases. OBJECTIVE: This study aimed to assess whether amniotic fluid microRNAs could be useful as biomarkers to identify pregnancies at greatest risk for severe recipient cardiomyopathy associated with twin-twin transfusion syndrome. STUDY DESIGN: Amniotic fluid was collected at the time of amnioreduction or selective fetoscopic laser photocoagulation from monochorionic diamniotic twin pregnancies with twin-twin transfusion syndrome at any stage. Fetal echocardiography was performed on all twins before the procedure, and severe cardiomyopathy was defined as a right ventricular myocardial performance index of the recipient fetus of >4 Z-scores. microRNA was extracted from the amniotic fluid samples and analyzed using an array panel assessing 379 microRNAs (TaqMan Open Array, ThermoFisher). Student t tests were performed to determine significant differences in microRNA expression between pregnancies with severe recipient cardiomyopathy and those with preserved cardiac function. A stringent q value of <.0025 was used to determine differential microRNA expression. Random forest plots identified the top 3 microRNAs that separated the 2 groups, and hierarchical cluster analysis was used to determine if these microRNAs properly segregated the samples according to their clinical groups. RESULTS: A total of 14 amniotic fluid samples from pregnancies with twin-twin transfusion syndrome with severe cardiomyopathy were compared with samples from 12 twin-twin transfusion syndrome control cases with preserved cardiac function. A total of 110 microRNAs were identified in the amniotic fluid samples. Twenty microRNAs were differentially expressed, and the top 3 differentiating microRNAs were hsa-miR-200c-3p, hsa-miR-17-5p, and hsa-miR-539-5p. Hierarchical cluster analysis based on these top 3 microRNAs showed a strong ability to differentiate severe cardiomyopathy cases from controls. The top 3 microRNAs were used to investigate the sensitivity and specificity of these microRNAs to differentiate between the 2 groups with a receiver operating characteristic curve demonstrating sensitivity and specificity of 80.8%. All 20 differentially expressed microRNAs were down-regulated in the group with severe cardiomyopathy. CONCLUSION: Amniotic fluid microRNAs demonstrated differential expression between twin-twin transfusion syndrome recipient fetuses with severe cardiomyopathy and those without and have the potential to be important biomarkers of disease severity in this population.

Maternal Amino Acid Profiles to Distinguish Constitutionally Small versus Growth-Restricted Fetuses Defined by Doppler Ultrasound: A Pilot Study.

OBJECTIVE: Fetuses measuring below the 10th percentile for gestational age may be either constitutionally small for gestational age (SGA) or have pathologic fetal growth restriction (FGR). FGR is associated with adverse outcomes; however, identification of low-risk SGA cases is difficult. We performed a pilot study evaluating maternal markers of pathologic FGR, hypothesizing there are distinct amino acid signatures that might be used for diagnosis and development of new interventions. STUDY DESIGN: This was a cohort study of healthy women with sonographic fetal estimated fetal weight <5th percentile divided into two groups based upon umbilical artery (UmA) Doppler studies or uterine artery (UtA) Doppler studies. We collected maternal blood samples prior to delivery and used ion pair reverse phase liquid chromatography-mass spectrometry or gas chromatography-mass spectrometry to assess 44 amino acids. RESULTS: Among 14 women included, five had abnormal UmA, and three had abnormal UtA Doppler results. Those with abnormal UmA showed elevated ornithine. Those with abnormal UtA had lower dimethylglycine, isoleucine, methionine, phenylalanine, and 1-methylhistidine. CONCLUSION: We found several amino acids that might identify pregnancies affected by pathologic FGR. These findings support the feasibility of future larger studies to identify maternal metabolic approaches to accurately stratify risk for small fetuses.

Examination of Prenatal Sonographic Findings: Intra-Abdominal Bowel Dilation Predicts Poor Gastroschisis Outcomes.

BACKGROUND: Gastroschisis is an anterior abdominal wall defect with variable outcomes. There are conflicting data regarding the prognostic value of sonographic findings. OBJECTIVES: The aim of this study was to identify prenatal ultrasonographic features associated with poor neonatal outcomes. METHOD: A retrospective review of 55 patients with gastroschisis from 2007 to 2017 was completed. Ultrasounds were reviewed for extra-abdominal intestinal diameter (EAID) and intra-abdominal intestinal diameter (IAID), echogenicity, visceral content within the herniation, amniotic fluid index, defect size, and abdominal circumference (AC). Ultrasound variables were correlated with full enteral feeding and the diagnosis of a complex gastroschisis. RESULTS: Bivariate analysis demonstrated an increased time to full enteral feeds with increasing number of surgeries, EAID, and IAID. Additionally, there was a significant relationship between IAID and AC percentile with the diagnosis of complex gastroschisis. On multivariate analysis, only IAID was significant and increasing diameter had a 2.82 (95% CI 1.02-7.78) higher odds of a longer time to full enteral feeds and a 1.2 (95% CI 1.05-1.36) greater odds of the diagnosis of a complex gastroschisis. CONCLUSIONS: Based on these findings, IAID is associated with a longer time to full enteral feeding and the diagnosis of complex gastroschisis.

Outcomes of Airway Management in Micrognathia and Retrognathia Patients Born at Fetal versus Nonfetal Centers.

OBJECTIVES: There is a paucity of evidence to guide the perinatal management of difficult airways in fetuses with micrognathia. We aimed to (1) develop a postnatal grading system based on the extent of airway intervention required at birth to assess the severity of micrognathic airways and (2) compare trends in airway management and outcomes by location of birth [nonfetal center (NFC), defined as a hospital with or without an NICU and no fetal team, versus fetal center (FC), defined as a hospital with an NICU and fetal team]. METHODS: We retrospectively reviewed the prenatal and postnatal records of all neonates diagnosed with micrognathia from January 2010 to April 2018 at a quaternary children's hospital. We developed a novel grading scale, the Micrognathia Grading Scale (MGS), to grade the extent of airway intervention at birth from 0 (no airway intervention) to 4 (requirement of EXIT or advanced airway instrumentation for airway securement). RESULTS: We identified 118 patients with micrognathia. Eighty-nine percent (105/118) were eligible for grading using the MGS. When the MGS was applied, the airway grades were as follows: grade 0 (30%), grade 1 (10%), grade 2 (9%), grade 3 (48%), and grade 4 (4%). A quarter of micrognathic patients with grade 0-2 airways had postnatal hospital readmissions for airway obstruction after birth, of which all were born at NFC. Over 40% of patients with grade 3-4 micrognathic airways required airway intervention within 24 h of birth. Overall, NFC patients had a readmission rate of (27%) for airway obstruction after birth compared to FC patients (17%). CONCLUSIONS: Due to the high incidence of grade 3-4 airways on the MGS in micrognathic patients, fetuses with prenatal findings suggestive of micrognathia should be referred to a comprehensive fetal care center capable of handling complex neonatal airways. For grade 0-2 airways, infants frequently had postnatal complications necessitating airway intervention; early referral to a multidisciplinary team for both prenatal and postnatal airway management is recommended.

Indomethacin Dosing and Constriction of the Ductus Arteriosus During Open Fetal Surgery for Myelomeningocele Repair.

INTRODUCTION: The use of perioperative tocolytic agents in fetal surgery is imperative to prevent preterm labor. Indomethacin, a well-known tocolytic agent, can cause ductus arteriosus (DA) constriction. We sought to determine whether a relationship exists between preoperative indomethacin dosing and fetal DA constriction. MATERIALS AND METHODS: This is an IRB-approved, single-center retrospective observational case series of 42 pregnant mothers who underwent open fetal myelomeningocele repair. Preoperatively, mothers received either 1 (QD) or 2 (BID) indomethacin doses. Maternal anesthetic drug exposures and fetal cardiac dysfunction measures were collected from surgical and anesthesia records and intraoperative fetal echocardiography. Pulsatility Index was used to calculate DA constriction severity. Comparative testing between groups was performed using t- and chi-square testing. RESULTS: DA constriction was observed in all fetuses receiving BID indomethacin and in 71.4% of those receiving QD dosing (p = 0.0002). Severe DA constriction was observed only in the BID group (35.7%). QD indomethacin group received more intraoperative magnesium sulfate (p < 0.0001). Minimal fetal cardiac dysfunction (9.5%) and bradycardia (9.5%) were observed in all groups independent of indomethacin dosing. CONCLUSIONS: DA constriction was the most frequent and severe in the BID indomethacin group. QD indomethacin and greater magnesium sulfate dosing was associated with reduced DA constriction.

MOMS Plus: Single-Institution Review of Outcomes for Extended BMI Criteria for Open Fetal Repair of Myelomeningocele.

BACKGROUND: In utero repair has become an accepted therapy to decrease the rate of ventriculoperitoneal shunting and improve neurologic function in select cases of myelomeningocele. The Management of Myelomeningocele Study (MOMS) trial excluded patients with a BMI >35 due to concerns for increased maternal complications and preterm delivery, limiting the population that may benefit from this intervention. OBJECTIVES: The aim of this study was to evaluate outcomes associated with extending the maternal BMI criteria to 40 in open fetal repair of myelomeningocele. METHOD: Retrospective review of fetal closure of myelomeningocele at a quaternary referral center between 2013 and 2016 with maternal BMI ranging from 35 to 40. RESULTS: Eleven patients with a BMI >35 were identified. The average BMI was 37. The average maternal age at the time of evaluation was 27 years. The average gestational age at fetal surgery was 24 weeks. Gestational age at birth was an average of 32 weeks. There was one perinatal death immediately following the fetal intervention. The shunt rate at 1 year was 45% (5/11 patients). CONCLUSIONS: In this single-institution review of expanded BMI criteria for fetal repair of myelomeningocele, we did not observe any adverse maternal outcomes associated with maternal obesity; however, the gestational age at delivery was 2 weeks earlier compared to the MOMS trial.

A cautionary response to SMFM statement: pharmacological treatment of gestational diabetes.

Use of oral agents to treat gestational diabetes mellitus remains controversial. Recent recommendations from the Society for Maternal-Fetal Medicine assert that metformin may be a safe first-line alternative to insulin for gestational diabetes mellitus treatment and preferable to glyburide. However, several issues should give pause to the widespread adoption of metformin use during pregnancy. Fetal concentrations of metformin are equal to maternal, and metformin can inhibit growth, suppress mitochondrial respiration, have epigenetic modifications on gene expression, mimic fetal nutrient restriction, and alter postnatal gluconeogenic responses. Because both the placenta and fetus express metformin transporters and exhibit high mitochondrial activity, these properties raise important questions about developmental programming of metabolic disease in offspring. Animal studies have demonstrated that prenatal metformin exposure results in adverse long-term outcomes on body weight and metabolism. Two recent clinical randomized controlled trials in women with gestational diabetes mellitus or polycystic ovary syndrome provide evidence that metformin exposure in utero may produce a metabolic phenotype that increases childhood weight or obesity. These developmental programming effects challenge the conclusion that metformin is equivalent to insulin. Although the Society for Maternal-Fetal Medicine statement endorsed metformin over glyburide if oral agents are used, there are few studies directly comparing the 2 agents and it is not clear that metformin alone is superior to glyburide. Moreover, it should be noted that prior clinical studies have dosed glyburide in a manner inconsistent with its pharmacokinetic properties, resulting in poor glycemic control and high rates of maternal hypoglycemia. We concur with the American Diabetes Association and American Congress of Obstetricians and Gynecologists, which recommend insulin as the preferred agent, but we believe that it is premature to embrace metformin as equivalent to insulin or superior to glyburide. Due to the uncertainty of the long-term metabolic risks of either metformin or glyburide, we call for carefully controlled studies that optimize oral medication dosing according to their pharmacodynamic and pharmacokinetic properties in pregnancy, appropriately target medications based on individual patterns of hyperglycemia, and follow the offspring long-term for metabolic risk.

Modified Hysterotomy Closure Technique for Open Fetal Surgery.

OBJECTIVE: We reviewed our experience with open fetal surgical myelomeningocele repair to assess the efficacy of a new modification of the hysterotomy closure technique regarding hysterotomy complication rates at the time of cesarean delivery. METHODS: A modification of the standard hysterotomy closure was performed on all patients undergoing prenatal myelomeningocele repair. The closure consisted of an interrupted full-thickness #0 polydioxanone (PDS) retention suture as well as a running #0 PDS suture to re-approximate the myometrial edges, and the modification was a third imbricating layer resulting in serosal-to-serosal apposition. A standard omental patch was placed per our routine. Both operative reports and verbal descriptions of hysterotomy from delivering obstetricians were reviewed. RESULTS: A total of 49 patients underwent prenatal repair of myelomeningocele, 43 having adequate follow-up for evaluation. Of those, 95.4% had completely intact hysterotomy closures, with only 1 partial dehiscence (2.3%) and 1 thinned scar (2.3%). There were no instances of uterine rupture. DISCUSSION: In patients undergoing this modified hysterotomy closure technique, a much lower than expected complication rate was observed. This simple modified closure technique may improve hysterotomy healing and reduce obstetric morbidity.