Frequency of Fetal Anomalies in Pregnancy Complicated by Polyhydromnios

Abstract

Background: Polyhydramnios is a condition characterized by an excessive accumulation of amniotic fluid, defined as a deepest vertical pool measuring 8 cm or more, or an amniotic fluid index (AFI) equal to or greater than 24 cm, which corresponds to values above the 95th centile for gestational age. The AFI is determined by calculating the deepest vertical pool in each of the four quadrants of the pregnant patient’s abdomen. Based on AFI values, polyhydramnios is classified into three categories: mild, with an AFI of 24–29.9 cm; moderate, with an AFI of 30–34.9 cm; and severe, with an AFI of 35 cm or more. Incidence 0.2%–3.9% of pregnancies and can arise from diverse maternal or fetal conditions. Idiopathic polyhydramnios, where no identifiable cause exists, poses significant diagnostic and management challenges, as it may be associated with adverse fetal outcomes and congenital anomalies.  Objective: This study aimed to determine the frequency and types of fetal anomalies in pregnancies complicated by polyhydramnios to aid in clinical risk assessment and management.  Methods: A cross-sectional study was conducted at Moula Bakhsh Hospital, Sargodha, from January 15 to June 15, 2025. A total of 149 pregnant women beyond 28 weeks’ gestation with polyhydramnios were enrolled through consecutive sampling. Participants underwent detailed history, examination, and targeted ultrasonography to detect fetal anomalies. Data were analyzed using SPSS 25, with Chi-square tests for statistical associations.  Results: Fetal anomalies were detected in 41 (27.5%) cases. Central nervous system anomalies (31.7%) were most common, followed by genitourinary (21.9%), and musculoskeletal (19.5%), gastrointestinal (12.2%) anomalies. Significant associations were found between fetal anomalies and history of congenital anomalies (p = 0.016) and polyhydramnios in previous pregnancies (p = 0.041), while maternal age and BMI showed no significant relationship. Conclusion: Polyhydramnios is associated with a high prevalence of fetal anomalies, emphasizing the need for thorough prenatal assessment. Systematic ultrasound evaluation and consideration of maternal history can enhance early detection and management of these high-risk pregnancies.