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.

Predictors of Poor Outcomes in Monochorionic Diamniotic Twin Pregnancies Complicated by Selective Fetal Growth Restriction.

INTRODUCTION: The aim of the study was to identify predictors of poor outcomes in monochorionic diamniotic twin (MCDA) pregnancies with selective fetal growth restriction (sFGR), irrespective of the umbilical artery (UA) Doppler abnormalities. METHODS: Single-center retrospective analysis of MCDA twins diagnosed with sFGR that opted for expectant management between 2010 and 2021. The presence of any of the following variables in the growth-restricted fetus: low amniotic fluid volume (DVP ≤2 cm), lack of a cycling bladder, absent or reversed flow in the ductus venosus (DV) with atrial contraction, and elevated middle cerebral artery peak systolic velocity (MCA-PSV) defined as ≥1.50 multiples of the median was categorized as complicated. sFGR cases were classified as simple in the absence of the above-mentioned variables. RESULTS: Overall, 63.3% of cases qualified as simple, and 36.7% were complicated. Intertwin EFW discordance was higher in the complicated category (26 vs. 33%, p = 0.0002). The median gestational age at delivery was earlier (33 weeks vs. 30.5 weeks, p = 0.002), and the likelihood of survival was lower in the complicated category (p < 0.0001). The likelihood of two survivors to discharge was lower in type I complicated cases (70% in complicated type I vs. 97.1% in simple type I, p = 0.0003). On logistic regression analysis, an increase in the "complicated" score negatively correlated with two survivors to discharge (p < 0.0001). An ROC curve was created, and the AUC was 0.79. Increasing intertwin EFW discordance also decreased the probability of two survivors to discharge. CONCLUSION: The presence of oligohydramnios, lack of a cycling bladder, abnormal DV Doppler, and elevated MCA-PSV in the growth restricted fetus is associated with poor perinatal outcomes and a lower likelihood of having two survivors to discharge. The addition of intertwin EFW discordance to these variables helped improve the survival predictability.

Amnioreduction vs expectant management in pregnancies with moderate to severe polyhydramnios.

BACKGROUND: The rate of polyhydramnios is higher in pregnancies complicated by congenital anomalies. These pregnancies have higher rates of peripartum complications. Amnioreduction is offered to relieve maternal symptoms such as dyspnea, abdominal and respiratory discomfort, and other issues like satiety. OBJECTIVE: This study aimed to report the rates of amnioreduction and its associated complications in pregnancies with moderate to severe polyhydramnios secondary to fetal anomalies. We also sought to determine if amnioreduction provided additional benefits, including prolongation of pregnancy and a decrease in the rates of peripartum morbidities associated with moderate to severe polyhydramnios. STUDY DESIGN: This was a retrospective review of anomalous singleton pregnancies with moderate to severe polyhydramnios that were evaluated and delivered at a single center between 2013 and 2021. Peripartum outcomes were compared between pregnancies that underwent amnioreduction and those that were expectantly managed. Mann-Whitney U tests were used to compare continuous variables and Fisher's exact tests were used for categorical variables. A multiple regression model was created to understand the effects of amnioreduction on gestational age at delivery. RESULTS: A total of 218 singleton pregnancies met the inclusion criteria of moderate to severe polyhydramnios in the study period. Of those, 110 patients (50.5%) underwent amnioreduction and 108 patients (49.5%) opted for expectant management. A total of 147 procedures were performed at a median gestational age of 32.5 weeks and a median of 1900 mL of amniotic fluid was removed per procedure. Complications occurred in 10.9% (n=16) of procedures, including preterm delivery within 48 hours in 5.4% cases (n=8). The median amniotic fluid index was higher in the amnioreduction group than in the expectant group (38.9 cm vs 35.5 cm; P<.0001). Patients who underwent amnioreduction had an earlier median gestational age at delivery (36.3 weeks vs 37.0 weeks; P=.048), however, the rates of spontaneous preterm delivery were similar. A higher percentage of women in the amnioreduction group had vaginal delivery (49.4% vs 30.5%; P=.01) and lower rates of uterine atony (2.4% vs 13.7%; P=.006). In the multiple linear regression analysis, the gestational age at delivery positively correlated with gestational age at amnioreduction after controlling for amniotic fluid volume (P<.0001; 95% confidence interval, 0.34-0.71). In addition, the patients in the amnioreduction group were twice as likely to have a vaginal delivery (P=.02). CONCLUSION: Amnioreduction in the setting of moderate-severe polyhydramnios has a reasonably low rate of complications but does not provide any benefits in terms of prolonging the pregnancy. The procedure may increase the likelihood of vaginal delivery and lower the rates of uterine atony.

Risks of Single Fetal Demise after Laser for Twin-Twin Transfusion Syndrome.

INTRODUCTION: The aim of the study was to determine if markers of donor placental insufficiency and recipient cardiac dysfunction increase the risk for single fetal demise (SFD) after laser for twin-twin transfusion syndrome (TTTS). METHODS: Single-center retrospective review of patients who had laser for TTTS. Risk factors for donor and recipient demise within 1 week were compared in pregnancies with SFD and pregnancies with dual survival using χ2 or Fisher's exact test. Multivariate logistic regression was then performed. RESULTS: Of 398 procedures, 305 (76.6%) had dual survival, 36 (9.0%) had donor demise, 28 (7.0%) had recipient demise, and 9 (2.3%) had dual demise. The remaining 20 (5.0%) patients had complicated courses with pregnancy loss or further intervention. In the 64 pregnancies with SFD, 29 (81%) in the donor group and 20 (71%) in the recipient group occurred in the first postoperative week. For the donor demise group, estimated fetal weight (EFW) <10%, EFW <3%, EFW <1%, EFW discordance >25%, and EFW discordance >30% did not increase the risk for donor demise except in cases that also had umbilical artery absent or reversed end diastolic flow (AREDF). Donor AREDF was the only independent risk factor for early donor demise. For the recipient demise group, recipient abnormal venous Dopplers were associated with increased risk while EFW discordance >25% was associated with decreased risk of recipient loss. DISCUSSION/CONCLUSION: In our cohort, donor growth restriction did not increase the risk of early donor demise after laser unless there was also donor AREDF. Donor AREDF was an independent risk factor for donor demise likely due to the severity of placental insufficiency. Abnormal recipient venous Doppler indices increased the risk of early recipient loss while a large intertwin discordance decreased the risk. This may be explained by profound overload in cases with recipient abnormal venous Doppler velocimetry and a lower risk of substantial fluid shifts from a relatively smaller donor territory when there is a large discordance.

Impact of Obesity on Pregnancies Undergoing Laser Therapy for Twin-Twin Transfusion Syndrome.

INTRODUCTION: We sought to determine if maternal obesity, defined by body mass index (BMI) 30-34.9 or BMI ≥35, negatively impacts the technical aspects and pregnancy outcomes in women treated with selective laser photocoagulation of placental communicating vessels for twin-twin transfusion syndrome (TTTS). METHODS: Retrospective review of women undergoing laser for TTTS from January 2010 to December 2021. Outcomes were stratified based on maternal BMI <30, 30-34.9, and ≥35. Data obtained included maternal age, parity, ethnicity, gestational age at laser, placental location, Quintero stage, CHOP cardiovascular score, operative and anesthesia times, procedure-to-delivery interval, gestational age at delivery, survival to birth, survival to discharge, and the presence of residual anastomoses. Statistical analysis included the χ2 or Fisher's exact test for categorical variables and the Mann-Whitney U test for continuous variables with p < 0.05 being significant. RESULTS: A total of 434 women underwent laser for TTTS during the study period. Of those, 274 (63%) had a BMI of <30, 92 (21.2%) had a BMI between 30 and 34.9, and 68 (15.7%) had a BMI ≥ 35. There were no differences in maternal age, parity or ethnicity, Quintero stage, CHOP cardiovascular score, placental location, operative time, laser-to-delivery interval, gestational age at delivery, survival outcomes, or the presence of residual anastomoses between the three groups. Patients with a BMI of 30-34.9 were operated on at a slightly later gestational age, and those with a BMI > 35 had longer operative and anesthesia times. There were no technical failures as a result of BMI ≥ 30 or 35. CONCLUSION: Using appropriate technical adjustments, outcomes for obese women undergoing laser for TTTS are similar to nonobese women, although patients with BMI ≥35 have longer operative and anesthesia times.

A critical role of hepatic GABA in the metabolic dysfunction and hyperphagia of obesity.

Hepatic lipid accumulation is a hallmark of type II diabetes (T2D) associated with hyperinsulinemia, insulin resistance, and hyperphagia. Hepatic synthesis of GABA, catalyzed by GABA-transaminase (GABA-T), is upregulated in obese mice. To assess the role of hepatic GABA production in obesity-induced metabolic and energy dysregulation, we treated mice with two pharmacologic GABA-T inhibitors and knocked down hepatic GABA-T expression using an antisense oligonucleotide. Hepatic GABA-T inhibition and knockdown decreased basal hyperinsulinemia and hyperglycemia and improved glucose intolerance. GABA-T knockdown improved insulin sensitivity assessed by hyperinsulinemic-euglycemic clamps in obese mice. Hepatic GABA-T knockdown also decreased food intake and induced weight loss without altering energy expenditure in obese mice. Data from people with obesity support the notion that hepatic GABA production and transport are associated with serum insulin, homeostatic model assessment for insulin resistance (HOMA-IR), T2D, and BMI. These results support a key role for hepatocyte GABA production in the dysfunctional glucoregulation and feeding behavior associated with obesity.

Hepatocyte membrane potential regulates serum insulin and insulin sensitivity by altering hepatic GABA release.

Hepatic lipid accumulation in obesity correlates with the severity of hyperinsulinemia and systemic insulin resistance. Obesity-induced hepatocellular lipid accumulation results in hepatocyte depolarization. We have established that hepatocyte depolarization depresses hepatic afferent vagal nerve firing, increases GABA release from liver slices, and causes hyperinsulinemia. Preventing hepatic GABA release or eliminating the ability of the liver to communicate to the hepatic vagal nerve ameliorates the hyperinsulinemia and insulin resistance associated with diet-induced obesity. In people with obesity, hepatic expression of GABA transporters is associated with glucose infusion and disposal rates during a hyperinsulinemic euglycemic clamp. Single-nucleotide polymorphisms in hepatic GABA re-uptake transporters are associated with an increased incidence of type 2 diabetes mellitus. Herein, we identify GABA as a neuro-hepatokine that is dysregulated in obesity and whose release can be manipulated to mute or exacerbate the glucoregulatory dysfunction common to obesity.

The Role of GPR109a Signaling in Niacin Induced Effects on Fed and Fasted Hepatic Metabolism.

Signaling through GPR109a, the putative receptor for the endogenous ligand ß-OH butyrate, inhibits adipose tissue lipolysis. Niacin, an anti-atherosclerotic drug that can induce insulin resistance, activates GPR109a at nM concentrations. GPR109a is not essential for niacin to improve serum lipid profiles. To better understand the involvement of GPR109a signaling in regulating glucose and lipid metabolism, we treated GPR109a wild-type (+/+) and knockout (-/-) mice with repeated overnight injections of saline or niacin in physiological states characterized by low (ad libitum fed) or high (16 h fasted) concentrations of the endogenous ligand, ß-OH butyrate. In the fed state, niacin increased expression of apolipoprotein-A1 mRNA and decreased sterol regulatory element-binding protein 1 mRNA independent of genotype, suggesting a possible GPR109a independent mechanism by which niacin increases high-density lipoprotein (HDL) production and limits transcriptional upregulation of lipogenic genes. Niacin decreased fasting serum non-esterified fatty acid concentrations in both GPR109a +/+ and -/- mice. Independent of GPR109a expression, niacin blunted fast-induced hepatic triglyceride accumulation and peroxisome proliferator-activated receptor α mRNA expression. Although unaffected by niacin treatment, fasting serum HDL concentrations were lower in GPR109a knockout mice. Surprisingly, GPR109a knockout did not affect glucose or lipid homeostasis or hepatic gene expression in either fed or fasted mice. In turn, GPR109a does not appear to be essential for the metabolic response to the fasting ketogenic state or the acute effects of niacin.

PKCγ, role in lens differentiation and gap junction coupling.

PURPOSE: To determine the role of PKCγ in the regulation of gap junction coupling in the normal lens, we have compared the properties of coupling in lenses from wild type (WT) and PKC-γ knockout (KO) mice. METHODS: Western blotting, confocal immunofluorescence microscopy, immunoprecipitation, RT-PCR and quantitative real time PCR were used to study gap junction protein and message expression; gap junction coupling conductance and pH gating were measured in intact lenses using impedance studies. RESULTS: There were no gross differences in size, clarity, or expression of full-length Cx46 or Cx50 in lenses from WT and PKCγ KO mice. However, total Cx43 protein expression was ~150% higher in the KO lenses. In WT lenses, Cx43 was found only in epithelial cells whereas in KO lenses, its expression continued into the fiber cells. Gap junction coupling conductance in the differentiating fibers (DF) of PKCγ KO lenses was 34% larger than that of WT. In the mature fiber (MF), the effect was much larger with the KO lenses having an 82% increase in coupling over WT. pH gating of the DF fibers was not altered by the absence of PKCγ. CONCLUSION: PKCγ has a major role in the regulation of gap junction expression and coupling in the normal lens.