EVALUATION OF UMBILICAL ARTERY DOPPLER INDICES IN NORMAL PREGNANCIES IN A NIGERIAN POPULATION

Background: Umbilical artery (UbA) Doppler sonography is a potential screening tool for pregnancy complications in placenta insufficiency. Assessment of the maternal and fetal vessels in pregnancy ensures accurate identification and prediction of pregnancy complications, such as preeclampsia (PE) and intrauterine growth restrictions (IUGR). The study aims to establish local reference values for UbA in a Nigerian population. Methods: A prospective longitudinal study was conducted among 230 pregnant women between April 2021 and March 2022. All participants had their fetal umbilical artery UbA evaluated with a Doppler ultrasound from 11 to 30 weeks 6 days of gestational age. Peak systolic velocity (PSV), End diastolic Velocity (EDV), Systolic/Diastolic ratio (S/D), Pulsatility Index (PI), and Resistivity Index (RI) were measured and documented. Results: The mean umbilical artery (UbA) Doppler indices at 11 weeks 0 day - 30 weeks 6 days GA ranged as follows 0.87 - 0.65 (RI), 2.53 - 1.05(PI), 16.42 - 2.84 (S/D ratio), 41.37 - 64.86 cm/s (PSV) & 16.27 - 20.93 cm/s (EDV) respectively. Conclusion: The umbilical artery Doppler reference range was established in the study population. These reference ranges will be of clinical value in daily obstetric and sonography practice. It is our opinion that data from this study will be beneficial to obstetricians, sonographers, and researchers in the evaluation of the umbilical arteries and the possible prediction and management of pregnancies in a similar population.