Use of β‐blockers during early pregnancy not linked to malformations

Exposure to β‐blockers during early pregnancy does not appear to result in congenital malformations or heart malformations in offspring, a study has shown.

“Beta-blockers are commonly used to treat hypertension that arises during pregnancy,” according to the investigators.

A systematic literature search was conducted in PubMed, Embase, and Cochrane Library from database inception until February 2020. The investigators identified observational studies assessing the associations between maternal β‐blocker use and congenital malformations in the meta-analysis.

Two reviewers independently extracted data and evaluated the quality of studies. A meta-analysis of outcomes was performed, and a summary odds ratio (OR) was calculated while considering heterogeneity.

Twenty observational studies met the eligibility criteria. Use of β‐blockers during early pregnancy did not correlate with an increased risk of congenital malformations (OR, 1.01, 95 percent confidence interval [CI], 0.93–1.09).

In subgroup analysis of organ-specific malformations, β‐blocker use correlated with an increased risk of heart malformations (OR, 1.29, 95 percent CI, 1.02–1.63) and a heightened risk of cleft lip or palate (OR, 1.5, 95 percent CI, 1.18–1.91). However, these associations (for heart malformations: OR, 1.11, 95 percent CI, 0.94–1.32; for cleft lip or palate: OR, 1.34, 95 percent CI, 0.98–1.85) did not persist after pooling the adjusted data.

In addition, β‐blocker use did not increase the risks of central nervous system malformations, neural tube defects, or hypospadias.

“Other organ‐specific congenital malformations should be evaluated in further studies,” the investigators said.