Distribution of Maternal High-Risk Factors Across Amniotic Fluid Volume Categories in High-Risk Pregnancies

Abstract

Background: Amniotic fluid volume abnormalities are common in high-risk pregnancies and reflect underlying maternal and fetal conditions, yet the distribution of specific maternal risk factors across different amniotic fluid categories remains insufficiently characterized. Objective: To evaluate the frequency and distribution of maternal high-risk factors across normal amniotic fluid volume, oligohydramnios, and polyhydramnios in high-risk pregnancies. Methods: This cross-sectional observational study included 81 high-risk pregnant women at ≥28 weeks gestation. Amniotic fluid volume was assessed using the amniotic fluid index and categorized as normal (5–25 cm), oligohydramnios (<5 cm), or polyhydramnios (>25 cm). Maternal risk factors, including hypertension, diabetes mellitus, preeclampsia, obstetric history, intrauterine growth restriction, and congenital anomalies, were recorded. Associations were analyzed using chi-square tests and odds ratios with 95% confidence intervals. Results: Normal amniotic fluid volume was observed in 60.5% of cases, oligohydramnios in 19.8%, and polyhydramnios in 19.8%. Intrauterine growth restriction was significantly associated with oligohydramnios (31.2% vs 8.2%; OR 5.13, p=0.02), while diabetes mellitus was strongly associated with polyhydramnios (37.5% vs 10.2%; OR 5.28, p=0.02). Hypertension and preeclampsia showed higher prevalence in oligohydramnios but were not statistically significant. The presence of ≥2 risk factors was associated with a threefold increase in abnormal amniotic fluid volume (OR 3.24, p=0.03). Conclusion: Maternal high-risk factors exhibit distinct distribution patterns across amniotic fluid categories, with oligohydramnios linked to placental insufficiency-related conditions and polyhydramnios associated with metabolic and structural factors. These patterns support targeted clinical evaluation and improved risk stratification.