Ultrasonographic Correlation of Placental Thickness With Gestational Age

Background: The placenta is a vital organ in pregnancy, and its sonographic thickness has emerged as a supplementary parameter for assessing gestational age (GA) and fetal well-being. This study aimed to evaluate the correlation of placental thickness with gestational age and standard fetal biometric parameters in antenatal women. Methods: A cross-sectional observational study was conducted on 200 antenatal women between 15 and 40 weeks of gestation at Sri Aurobindo Institute of Medical Sciences, Indore. Placental thickness was measured sonographically at the level of umbilical cord insertion during early (15–22 weeks) and late (30–40 weeks) scans. Biometric parameters including biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC), and femur length (FL) were also recorded. Statistical analyses were performed using Pearson's correlation, paired t-test, and linear regression. Results: A consistent and statistically signicant increase in placental thickness with gestational age was noted. In early scans, mean placental thickness rose from 1.743 cm at 15–18 weeks to 2.101 cm at 20–22 weeks. In late scans, it increased from 3.100 cm at 30–33 weeks to 3.802 cm at 36–40 weeks. Placental thickness showed strong positive correlations with gestational age (r = 0.775 in early, r = 0.613 in late scans; p < 0.001). Signicant correlations were also observed with fetal parameters—FL (r = 0.399), AC (r = 0.325), BPD (r = 0.293), and HC (r = 0.193) in late scans. The mean increase in placental thickness between early and late scans was 1.72 cm (p < 0.001). Conclusion: Placental thickness correlates signicantly with gestational age and fetal biometric measurements. It can be a reliable adjunct in estimating gestational age, especially when standard parameters are inconclusive.