A two-stage screening test for pregnancy-induced hypertension and preeclampsia.

OBJECTIVE: To assess the benefit of uterine artery Doppler ultrasound examination with ambulatory 24-hour blood pressure (BP) monitoring as a two-stage screening test for women at risk for pregnancy-induced hypertension, preeclampsia, or fetal growth restriction (FGR). METHODS: Uterine artery Doppler ultrasound was performed at 20-22 weeks' gestation on women at risk for pregnancy-induced hypertension, preeclampsia or FGR who were referred to our antenatal clinics. Abnormal findings were rechecked at 24 weeks' gestation. We selected 180 subjects (90 with abnormal uterine Doppler and 90 with normal uterine Doppler) for 24-hour BP monitoring with a portable automated device, immediately after recruitment, and the midline estimating statistics of rhythm of systolic and diastolic BPs were calculated. RESULTS: The highest incidence of pregnancy-induced hypertension and preeclampsia, with or without FGR, occurred in patients with abnormal uterine Doppler and a systolic midline estimating statistic of rhythm of at least 111 mmHg or a diastolic midline estimating statistic of rhythm of at least 68 mmHg. The specificity and positive predictive value of abnormal uterine Doppler ultrasound alone were low (55 and 27%, respectively), whereas the association of abnormal Doppler ultrasound with both systolic and diastolic midline estimating statistics of rhythm equal or above the selected cutoff values increased the specificity and positive predictive value to 93 and 63%, respectively. CONCLUSION: In clinical practice, a first-stage test with uterine artery Doppler ultrasound at 20-24 weeks' gestation, followed by a second-stage test with ambulatory 24-hour BP monitoring in patients with abnormal uterine Doppler, might indicate women at risk of developing pregnancy-induced hypertension or preeclampsia.