SONOGRAPHICAL EVALUATION OF PLACENTAL THICKNESS IN THIRD-TRIMESTER PREGNANCIES AND FETAL OUTCOMES

Abstract

Background: The placenta is a vital organ regulating gas exchange, nutrient delivery, and metabolic homeostasis between mother and fetus. Variations in placental thickness (PT) are associated with adverse fetal outcomes such as intrauterine growth restriction (IUGR) and low birth weight (LBW). However, localized clinical evidence from Khyber Pakhtunkhwa (KPK), Pakistan, remains limited. Objectives: To evaluate PT in third-trimester pregnancies using transabdominal ultrasonography and assess its clinical correlation with key fetal growth metrics, specifically estimated fetal weight, fetal size, and femur length. Methods: A prospective cross-sectional descriptive study was conducted over four months at the Radiology Department of Rehman Medical Institute, Peshawar. A total of 264 third-trimester pregnant women (≥27 gestational weeks) with singleton pregnancies were enrolled via non-probability convenience sampling. Transabdominal sonography (3.5–5 MHz) measured PT at cord insertion alongside fetal biometry. Associations were analyzed using Pearson Chi-Square tests and symmetric measures in SPSS v27. Results: PT exhibited a statistically significant correlation with estimated fetal weight (χ² = 18.72, df = 4, p = 0.001; Cramer's V = 0.188) and overall fetal size (χ² = 16.45, df = 4, p = 0.002; Cramer's V = 0.176). Higher PT was associated with normal and large-for-gestational-age categories, while reduced PT correlated with low birth weight. The association between PT and femur length demonstrated a positive trend but did not reach conventional statistical significance (χ² = 9.12, df = 4, p = 0.058). Conclusion: Ultrasonographic PT is a robust, non-invasive predictor of fetal weight and size in the third trimester. Integrating routine PT measurements into antenatal screening offers an effective method for early identification of growth aberrations, particularly in resource-constrained settings.