Significance of second-trimester uterine artery Doppler in predicting preeclampsia in South Indian pregnant women

Aim. To evaluate the usefulness of uterine artery Doppler screening in second-trimester gestation women for predicting the risk of preeclampsia, and to identify the sensitivity and specificity of the Doppler indices-notching and pulsatility index (PI). Method. This study is a prospective, observational study involving 250 second-trimester pregnant women (20–24 weeks) in the Department of Antenatal Clinic, KGH Hospital (Tertiary Health Care Centre), Triplicane, and the Institute of Obstetrics and Gynaecology, Egmore, Chennai, India, from February 2019 to December 2022. After obtaining consent and meeting inclusion criteria, the study participants' gestational age, antenatal investigation, BMI, blood pressure, clinical markers, proteinuria, impaired uterine artery flow, uterine artery Doppler (UAD), and preeclampsia status were observed and recorded. Results. A total of 250 women between 20–24 weeks of gestation were included in this study. Doppler imaging was used to predict the risk of preeclampsia using notching and pulsatility index as diagnostic tools. Out of the 250 participants, 192 women had negative notching, whereas 58 women had positive notching. Among the 192 participants with negative notching, 94.8% were preeclampsia-free, 90.1% of the preeclampsia-free population fell within this group, and the total percentage of preeclampsia-free subjects was 72.8%. Among the 58 participants with positive notching, 34.5% were preeclampsia-free, while 9.9% had preeclampsia, accounting for a total percentage of 8.0%. Overall, preeclampsia was present in 100% of the cases with positive notching. The specificity was 0.90099 (95% CI: 0.84–0.93), the false negative rate was 0.052083 (95% CI: 0.02–0.09), and the false positive rate was 0.344828 (95% CI: 0.22–0.48), demonstrating a significant correlation between notching and preeclampsia (χ² = 104.433, p-value < 0.000). The aggregate proportion within PI among the 250 cases was 100.0%. Despite this, there was no significant association between PI and preeclampsia. Conclusion. Our study participants in the second trimester demonstrated a strong association between notching and preeclampsia. Notching during the second trimester showed a sensitivity of 79% (95% CI: 64–89%) and a specificity of 90% (95% CI: 84–93%). With a p-value < 0.000, the positive predictive value was 65%, and the negative predictive value was 94% (χ² = 104.433). Preeclampsia and PI were not significantly correlated. Doppler is an important tool for forecasting preeclampsia in high-risk second-trimester pregnancies.