Gestational age

Bisoprolol

Obstetrics

Prospective cohort study

Birth weight

Cohort study

Blood pressure

Biology

Odds ratio

Gestation

Cohort

Internal medicine

Pediatrics

Pregnancy

Metoprolol

Genetics

Medicine

Journal of Hypertension

Our aim was to evaluate the effects of beta-blockers during the second and third trimester on fetal growth, length of gestation and postnatal symptoms in exposed infants.The current prospective observational cohort study compares 294 neonates of hypertensive mothers on metoprolol or bisoprolol during the second and/or third trimester with 225 methyldopa-exposed infants and 588 infants of nonhypertensive mothers. The risks for reduced birth weight, prematurity, neonatal bradycardia, hypoglycaemia and respiratory disorders were analysed.The rate of small-for-gestational-age children was significantly higher in long-term beta-blocker exposed infants (24.1%) compared with the methyldopa cohort [10.2%, odds ratio (OR)adj 2.5, 95% confidence interval (CI) 1.2-5.2] and the nonhypertensive cohort (9.9%, ORadj 4.3, 95% CI 2.6-7.1). The risk for preterm birth was significantly increased compared with nonhypertensive pregnancies (ORadj 2.2, 95% CI 1.3-3.8) but not compared with the methyldopa cohort. Neonatal adverse outcomes occurred more frequently in the study cohort (11.5%) compared with the nonhypertensive comparison group (6.5%) and the methyldopa cohort (8.4%), but without statistical significance (ORadj 1.5, 95% CI 0.7-3.0 and ORadj 1.5, 95% CI 0.7-3.3, respectively).Long-term intrauterine exposure to metoprolol or bisoprolol may increase the risk of being born small-for-gestational-age. It is still a matter of debate to which extent maternal hypertension contributes to the lower birth weight. Serious neonatal symptoms are rare. Altogether, metoprolol and bisoprolol are well tolerated treatment options, but a case-by-case decision on close neonatal monitoring is recommended.

Neonatal effects of intrauterine metoprolol/bisoprolol exposure during the second and third trimester: a cohort study with two comparison groups