Objective: To evaluate pregnancy outcomes in normotensive second pregnancy following pre-eclampsia in first pregnancy.
Design: Population-based retrospective cohort study.
Setting: State of Missouri in the USA.
Sample: White European origin or African-American women who delivered their first two non-anomalous singleton pregnancies between 20 and 44 weeks of gestation in Missouri, USA, 1989-2005, without chronic hypertension, renal disease or diabetes mellitus (n = 12 835).
Methods: Pre-eclampsia or delivery at 34 weeks of gestation or less in first pregnancy was defined as early-onset pre-eclampsia, whereas late-onset pre-eclampsia was defined as pre-eclampsia with delivery after 34 weeks of gestation. Multivariate regression models were fitted to estimate the crude and adjusted odds ratios and 95% confidence intervals.
Main outcome measures: Preterm delivery, large and small-for-gestational-age infant, Apgar scores at 5 minutes, fetal death, caesarean section, placental abruption.
Results: Women with early-onset pre-eclampsia in first pregnancy were more likely to be younger, African-American, recipients of Medicaid, unmarried and smokers. Despite a second normotensive pregnancy, women with early-onset pre-eclampsia in their first pregnancy had greater odds of a small-for-gestational-age infant, preterm birth, fetal death, caesarean section and placental abruption in the second pregnancy, relative to women with late-onset pre-eclampsia, after controlling for confounders. Moreover, maternal ethnic origin modified the association between early-onset pre-eclampsia in the first pregnancy and preterm births in the second pregnancy. Having a history of early-onset pre-eclampsia reduces the odds of having a large-for-gestational-age infant in the second pregnancy.
Conclusion: A history of early-onset pre-eclampsia is associated with increased odds of adverse pregnancy outcomes despite a normotensive second pregnancy.