Risks and benefits of beta-receptor blockers for pregnancy hypertension: overview of the randomized trials

Objective: Examine the benefits/risks of beta-blockers for pregnancy hypert ension. Study design: Meta-analysis of relevant trials identified by compre hensive literature review (1966-97). Results: Included were 30 trials for p regnancy hypertension, and four others for perinatal outcomes only. For mil d chronic hypertension treated throughout pregnancy (n=2 trials), oral beta -blockers (compared with no therapy) were associated with an inconsistent i ncrease in small for gestational age (SGA) infants (OR 2.46 [1.02, 5.92]), For mild-moderate 'late-onset' pregnancy hypertension (i.e. either chronic treated only late in pregnancy, or pregnancy-induced) (n=8 trials), oral be ta-blockers (compared with no therapy) were associated with a decrease in s evere hypertension (OR 0.27 [0.16, 0.45]), borderline decrease in developme nt of proteinuria (OR 0.69 [0.48, 1.02]), decrease in RDS (OR 0.33 [0.13, 0 .85]), but a borderline increase in SGA infants (OR 1.47 [0.96, 2.26]), bet a-blockers were equivalent to other agents (n=15 trials). For severe 'late- onset' pregnancy hypertension (n=5 trials), i.v. labetalol produced less ma ternal hypotension (OR 0.13 [0.03, 0.71]) and fewer cesareans (OR 0.23 [0.1 3, 0.63]) than i.v. hydralazine/diazoxide. Conclusions: It is not clear tha t the benefits outweigh the risks when beta-blockers are used to treat mild to moderate chronic or pregnancy-induced hypertension, given the unknown o verall effect on perinatal outcomes. For severe 'late-onset' pregnancy hype rtension, i.v. labetalol is safer than i.v. hydralazine or diazoxide, (C) 2 000 Elsevier Science Ireland Ltd. All rights reserved.