Preeclampsia and brain damage among preterm infants: a changed panorama in a 20-year analysis.

The purpose of this study was to compare the rates of preterm infant brain damage between preeclamptic and normotensive pregnancies during a 20-year period. A cohort study was performed of 1201 singleton pregnancies between 24 and 35 weeks gestation delivered at a single institution during the period 1984-2003. Preeclampsia was diagnosed according to standard criteria. Periventricular/intraventricular hemorrhage (PV-IVH) and periventricular leukomalacia were diagnosed by postnatal cranial ultrasound. Severe infant brain damage was defined as the presence of cystic periventricular leukomalacia and/or intraparenchymal hemorrhage or IVH with ventricular dilation. Logistic regression analysis was used to compute the rates of neonatal brain damage adjusting for potential confounders and to perform an interaction study. The crude rates of severe brain damage among the 329 preeclamptic pregnancies were 11.6% (five of 43) in the period 1984 to 1988 and 0.86% (one of 116) in the period 1999 to 2003 ( P for trend < 0.001). The adjusted decrement in the rate of severe brain damage per 5-year period was 65.7% (95% confidence interval [CI], 35.1 to 81.9). The crude rates of severe brain damage among the 872 normotensive pregnancies were 6.1% (eight of 132) in the period 1984 to 1988 and 3.4% (10 of 298) in the period 1999 to 2003 ( P for trend = 0.03). The adjusted decrement per 5-year period was 21.7 (95% CI, 10.6 to 31.4; P = 0.001 compared with infants born to mothers with preeclampsia). Multivariable analysis of interaction confirmed that, during the period of the study, the decrement in the rates of PV-IVH ( P for interaction = 0.04) and of severe brain damage ( P for interaction = 0.03) was higher among preeclamptic than normotensive pregnancies. At our institution, in the last two decades the decrement in the rates of PV-IVH and severe brain damage among preterm infants was significantly higher in preeclamptic than normotensive pregnancies.