Prevention of preeclampsia: A randomized trial of atenolol in hyperdynamicpatients before onset of hypertension

Objective: To determine if assessment of maternal hemodynamics could predic t women at risk for the development of preeclampsia, if treatment directed at hemodynamic abnormalities before the onset of hypertension could prevent preeclampsia, and if mothers could be treated in a way that protects fetal growth. Methods: A double-blinded, randomized controlled trial was conducted. Subje cts were considered to be at risk for preeclampsia if their cardiac output was greater than 7.4 L/min before 24 weeks' gestation. Nulliparous and diab etic subjects at risk were treated with 100 mg of atenolol or placebo. Card iac output was measured by Doppler technique. Inulin and para-aminohippurat e clearances were performed. Results: Treatment with atenolol reduced the incidence of preeclampsia from 5 of 28 (18%) to I of 28 (3.8%), (P = .04). Nulliparous women determined t o be at risk for preeclampsia were similar to diabetic women at risk. Each was significantly heavier and had inulin and para-aminohippurate clearances greater than the control group. Treatment with atenolol was associated wit h infants weighing 440 g less than infants in the nulliparous placebo group , (P = .02). No effect on birth weight was seen in the diabetic patients. M others of the smallest infants who were treated with atenolol could be iden tified by unexpectedly large reductions in cardiac output. Conclusion: Measurement of cardiac output in the second trimester identifie d women at risk for preeclampsia. Treatment with atenolol decreased the inc idence of preeclampsia. Nulliparous and diabetic women at risk for preeclam psia were similar with regard to maternal hemodynamics, maternal weight, an d renal function. Treatment with atenolol was associated with reduced infan t birth weight. (C) 1999 by The American College of Obstetricians and Gynec ologists.