Neonatal effects of beta-blocking drugs in pregnancy.

A review is presented as regards the neonatal effects of beta-blocking agents in hypertension during pregnancy. Experience points to low fetal and neonatal risks, but firmly based data concerning the neonates are very scanty. An on-going double-blind study is presented in which pregnant women with hypertension are randomly allocated to either metoprolol or placebo treatment. One of the aims is to study the postnatal adaptation of the infants. The following measurements, recordings and examinations are performed: anthropometric measurements, Apgar score, blood gases and acid-base status in umbilical (venous and arterial) blood, lactate and hypoxanthine in umbilical venous blood, catecholamines in umbilical arterial blood, pulse rate, blood glucose and a quantitative neurobehavioral assessment in the neonatal period.