Prediction of recurrence of hypertensive disorders of pregnancy between 34 and 37 weeks of gestation: A retrospective cohort study

Objective To assess the recurrence risk of late-preterm hypertensive disease of pregnancy, and to determine whether potential risk factors are predictive. Design Retrospective cohort study. Setting Three secondary and three tertiary care hospitals in the Netherlands. Population We identified women with a hypertensive disorder in the index pregnancy and delivery at 34-37 weeks of gestation, between January 2000 and December 2002. Methods Data were extracted from medical files and women were approached for additional information on subsequent pregnancies. An adverse outcome was defined as the recurrence of a hypertensive disorder in the next subsequent pregnancy. Main outcome measures Absolute risk of recurrence and a prediction model containing demographic and clinical factors predictive for adverse outcome. Results We identified 425 women who matched the criteria, of whom 351 could be contacted. Of these women, 189 (54%) had had a subsequent pregnancy. Hypertensive disorders recurred in 96 (51%, 95% CI 43-58%) women, of whom 17 (9%, 95% CI 5-14%) delivered again before 37 weeks of gestation. Chronic hypertension and maternal age were the strongest predictors for recurrence. Women undergoing recurrence had a nine-fold chance of developing chronic hypertension (37% versus 6%, OR 8.7, 95% CI 3.3-23). Conclusions Women with hypertensive disorders and late-preterm delivery have a 50% chance of recurrence, but only a 9% chance of recurrence resulting in delivery before 37 weeks of gestation. Women with chronic hypertension are prone to develop recurrence, and women with a recurrence more often developed chronic hypertension.