67 - Antenatal Ultrasound Findings and Trimester of Onset as Predictors of Neonatal Morbidity in Pregnancies Complicated by Polyhydramnios

Publication Number: 2064.67

Tara Lozy, Hackensack Meridian School of Medicine, Hackensack, NJ, United States; jeanette Haugh, Joseph M. Sanzari Children's Hospital Hackensack University Medical Center, Hackensack, NJ, United States; Nicole Feigenblum, Hackensack University Medical Center, Hackensack, NJ, United States; jesus Alvarez-Perez, Hackensack UMC, Hackensack, NJ, United States; Marwa Khalil, Hackensack Meridian School of Medicine, hackensack, NJ, United States; Pooja Bhate, Hackensack Meridian School of Medicine, Edison, NJ, United States

Background: Polyhydramnios complicates 1-3% of pregnancies and increases risks of preterm birth, malpresentation, and perinatal morbidity. Its etiology can be idiopathic or linked to significant fetal and maternal pathology. Antenatal ultrasound is the primary diagnostic tool, but its full potential to predict specific neonatal complications based on the timing and nature of the findings remains to be fully elucidated.

Objective: To assess the prognostic utility of antenatal ultrasound findings in predicting neonatal morbidity in pregnancies complicated by polyhydramnios.

Design/Methods: A single-center retrospective review was performed of pregnancies with AFI > 24 cm delivered between 2011 and 2022. Pregnancies with oligohydramnios, normal AFI, or multiple gestations were excluded. Maternal and neonatal data- including ultrasound AFI trends, biophysical profile, fetal Doppler, and perinatal outcomes- were collected. Associations were tested using Chi-square and Mann-Whitney U tests for categorical and continuous variables, respectively, with a significance threshold of 0.05. Results were stratified by presence of maternal risk factors and timing of diagnosis.

Results: Among 137 pregnancies with polyhydramnios, 59 had maternal risk factors and 78 were idiopathic. 2nd trimester diagnosis (n=22) was associated with lower birthweight (median 3160 g vs 3425 g, p 0.03), higher preterm labor (p < 0.001) and preterm premature rupture of membranes rates (p < 0.001), chromosomal and neurologic anomalies (p 0.0002 and 0.03, respectively), abdominal wall defects (p 0.02), neonatal death (4.6% vs 0%, p 0.02), and neurodevelopmental delays (18.2% vs 8.0%, p 0.02) compared with 3rd trimester cases (n=113). Maternal risk factors significantly correlated with earlier delivery (median: 38.0 wks vs 38.9 wks, p 0.004) and marginally correlated with increased electrolyte (p 0.07) and feeding concerns (p 0.05).

Conclusion(s): Preliminary results showed that 2nd trimester diagnosis was a stronger predictor of adverse neonatal outcomes than maternal risk factors, which were previously thought to drive outcomes. The basis for this early-severity relationship is unclear and warrants further study with larger cohorts. These findings underscore the utility of antenatal ultrasound not just for diagnostic purposes, but also for risk stratification of polyhydramnios by timing, which may improve prenatal counseling and guide delivery planning.