MATERNAL AND FETAL OUTCOMES IN LOW VERSUS NORMAL AMNIOTIC FLUID INDEX IN POST-DATE PREGNANCIES

Abstract

Background: Amniotic fluid assessment remains a fundamental component of obstetric evaluation, yet uncertainty persists regarding whether low Amniotic Fluid Index (AFI) in post-date pregnancies acts as an independent determinant of adverse outcomes or simply reflects underlying pathology. This ambiguity often leads to uniform clinical interventions that may not be tailored to individual risk. Given the widespread use of ultrasound-based AFI estimation in routine obstetric care, further clarification is essential to support informed decision-making and optimize perinatal outcomes.

Objective: To determine the fetomaternal outcomes of post-date pregnancies with low AFI and compare these outcomes with those of post-date pregnancies exhibiting normal AFI.

Methods: A descriptive study was conducted in the Department of Obstetrics and Gynecology, Khyber Teaching Hospital, Peshawar, from 1 January to 30 June 2023. A total of 156 women aged 20–40 years with gestational ages between 38 and 42 weeks were recruited and categorized into low-AFI (<5 cm) and normal-AFI groups based on ultrasonographic four-quadrant AFI measurement. Maternal outcomes included mode of delivery and wound infection, while fetal outcomes included low Apgar score at 5 minutes and low birth weight (<2500 g). Ethical approval was obtained, informed consent was ensured, and data were analyzed using SPSS v.26, with categorical variables compared using chi-square testing at a 5% significance level.

Results: Among the 156 participants, 54 (34.6%) had low AFI and 102 (65.4%) had normal AFI. The mean age was 31.04 ± 4.01 years in the low-AFI group and 32.04 ± 5.32 years in the normal-AFI group. Mean gestational age was 39.47 ± 1.17 weeks versus 39.86 ± 1.46 weeks, respectively. Low birth weight occurred in 18 (33.3%) women with low AFI compared with 10 (9.8%) in the normal-AFI group (p < 0.001). Low Apgar score (<7 at 5 minutes) was found in 22 (40.7%) versus 8 (7.8%) participants (p < 0.001). Cesarean delivery was required in 24 (44.4%) of low-AFI women compared with 12 (11.8%) with normal AFI (p < 0.001). Wound infection occurred in 12 (22.2%) and 12 (11.8%) women, respectively (p = 0.085).

Conclusion: Low AFI in post-date pregnancies was strongly associated with adverse fetal outcomes, particularly low birth weight and low Apgar scores, highlighting its significance as a marker of compromised intrauterine conditions. Maternal complications showed no statistically significant differences, suggesting that oligohydramnios primarily influences fetal well-being. Routine AFI assessment may therefore play a crucial role in risk stratification and timely obstetric intervention.