Comparing Doppler indices of umbilical artery in pregnancy-induced hypertension and normal pregnant women during the third trimester of pregnancy.

Abstract

Objective: To compare Doppler indices of umbilical artery - resistance index (RI), pulsatility index (PI), and systolic to diastolic (SD) ratio between pregnancies complicated by pregnancy induced hypertension (PIH) and normotensive pregnancies in the third trimester. Study Design: Comparative Cross-Sectional Study. Setting: Aziz Fatimah Hospital, Faisalabad, Pakistan. Period: June 2024 to December 2024. Methods: In this study, 100 singleton pregnancies (50 PIH, 50 normotensive) underwent ultrasound Doppler assessment at 32‑38 weeks’ gestation. Mean PI, RI, and S/D ratio were calculated for each group. Independent t-test and Mann-Whitney U test were applied, with significance at p < 0.05. Results: All Doppler indices were significantly higher in the PIH group (PI 1.26 ± 0.25; RI 0.72 ± 0.06; S/D 4.08 ± 0.58) than in normotensive controls (PI 0.81 ± 0.13; RI 0.55 ± 0.06; S/D 2.08 ± 0.27) (p < 0.001 for each). Elevated indices indicate increased placental vascular resistance consistent with impaired fetoplacental perfusion. Conclusion: Pregnancy‑induced hypertension is associated with significantly raised umbilical‑artery PI, RI, and S/D ratio, corroborating previous evidence of placental insufficiency in hypertensive pregnancies. Routine third‑trimester Doppler surveillance and serial monitoring of these indices may facilitate early intervention and improve perinatal outcomes.