Placental bed lesions and infant birth weight in hypertensive pregnant women.

Sixty pregnant women with systemic arterial hypertension, whose pregnancies were interrupted by cesarean section at the Maternity Ward of Hospital de Clínicas de Porto Alegre between May 1989 and October 1990, were examined. Specimens of the placental bed were collected by biopsy and the presence of acute atheromatosis and/or fibrinoid necrosis was investigated. The patients were divided into two groups according to the presence or absence of vascular lesions. The biopsy findings of the placental bed were compared with adequate weight at birth related to gestational age, and to the following clinical parameters of the mother: arterial blood pressure, serum creatinine, serum uric acid and proteinuria. Twenty-seven (45%) patients presented vascular lesions in the placental bed compatible with acute atheromatosis and/or fibrinoid necrosis. The presence of vascular changes in the placental bed correlated significantly to diminished weight of the newborn, in terms of the mean weight and in terms of small-for-gestational-age infants, non-nephrotic proteinuria ( > or = 300 mg/24 h) and increased levels of uric acid ( > 5.5 mg/dl).