Maternal history and uterine artery wave form in the prediction of early-onset and late-onset preeclampsia: A cohort study

Background: Pregnancy induced hypertension (PIH) is a significant cause of maternal morbidity and mortality. Pregnancy-induced-hypertension can be prevented by identification of prenatal and antenatal factors. The uterine artery Doppler waveform transforms into a high flow with low resistance at 22-24 wk.
Objective: To study the maternal risk factors and uterine artery Doppler waveform in singleton mid-trimester pregnancy and predict the occurrence of pregnancy-induced hypertension.
Materials and Methods: This is a cohort study comprising of Doppler ultrasound examination of the uterine arteries at 20-23 wk gestation in 697 women with singleton pregnancies attending a routine target scan. The pregnant women were followed up. PIH was recorded in 57 (8.18%) of all pregnancies.
Results: Maternal age >34 yr, primiparity, the presence of chronic hypertension was also associated with increased risk of PIH. High pulsatility index (>95^th percentile) as compared to low pulsatility index was a good tool for the detection of PIH (sensitivity 91.23% and specificity 99.06%, p<0.05). Presence of high pulsatility was a significant risk factor for early-onset PIH as compared to late-onset PIH.
Conclusion: Uterine artery Doppler can be safely performed at the time of routine target anomaly scan in the second trimester. It is simple, economical, feasible and with good detection rates.

Keywords
Hypertension; Preeclampsia; Trophoblasts; Ultrasonography; Doppler; Uterine artery.