SONOGRAPHIC COMPARISON OF FETAL HEART RATE IN GESTATIONAL HYPERTENSIVE AND NORMOTENSIVE MOTHERS IN THE SECOND AND THIRD TRIMESTER

Background: Hypertensive disorders during pregnancy are among the leading causes of maternal and fetal morbidity and mortality worldwide. These conditions can significantly alter maternal cardiovascular dynamics, which in turn may impact fetal heart rate (FHR)—a key indicator of fetal well-being. Monitoring FHR through sonographic techniques provides critical insights into fetal health, particularly in pregnancies complicated by gestational hypertension. Objective: To evaluate and compare fetal heart rate patterns between gestational hypertensive and normotensive mothers during the second and third trimesters using ultrasound imaging. Methods: A comparative analytical study was conducted at the Radiology Department of Services Hospital Lahore, Pakistan, over six months from February 2019 to July 2019. After obtaining ethical approval from the Institutional Review Committee of the University of Lahore, a total of 130 pregnant women in their second and third trimesters were enrolled through convenience sampling. Among them, 21 women (16.1%) were diagnosed with gestational hypertension and 109 (83.8%) were normotensive. All participants underwent standardized obstetric ultrasound using a MINDRAY-DP-22 machine with a 3.5 MHz convex transducer. Gestational age and FHR were assessed using a four-chamber cardiac view, and FHR was recorded using M-mode ultrasound. Descriptive statistics were reported using mean, standard deviation, and percentage, while group comparisons were analyzed using the independent samples t-test. Results: The mean fetal heart rate in gestational hypertensive mothers was significantly higher (173.71 ± 9.93 bpm) compared to normotensive mothers (150.23 ± 5.82 bpm) with a p-value of 0.000. The mean gestational age was 24.48 ± 3.20 weeks in the hypertensive group and 26.37 ± 4.16 weeks in the normotensive group. Most hypertensive cases occurred in the second trimester (n = 13, 16.4%) and among women aged 26–31 years. Conclusion: Fetal heart rate was markedly elevated in pregnancies complicated by gestational hypertension, particularly during the second trimester. These findings underscore the influence of maternal blood pressure on fetal autonomic regulation and reinforce the value of early and regular sonographic monitoring in hypertensive pregnancies.