Is metoprolol (beta blocker) safe during pregnancy?

From the Guidelines

Metoprolol is generally considered safe to use during pregnancy, but it should be used with caution and under close medical supervision. According to the most recent and highest quality study 1, metoprolol is not listed as a first-line antihypertensive agent during pregnancy, but it can be used as a second-line option when safer alternatives are not effective. The study suggests that first-line antihypertensive agents, such as extended-release nifedipine and labetalol, should be prioritized due to their more robust safety and efficacy data.

Some key points to consider when using metoprolol during pregnancy include:

• Metoprolol crosses the placenta and has been associated with potential risks, including intrauterine growth restriction, bradycardia in the fetus, and hypoglycemia in newborns 1.
• If metoprolol is deemed necessary during pregnancy, the lowest effective dose should be used, typically starting at 25-50 mg twice daily for hypertension, with careful monitoring of both maternal and fetal well-being 1.
• Blood pressure and fetal growth should be regularly assessed throughout pregnancy, and women taking metoprolol during pregnancy should not stop it abruptly without medical guidance, as this could lead to rebound hypertension or worsening cardiac symptoms 1.
• The safety concerns are greatest during the third trimester when fetal effects are most pronounced, and for women planning pregnancy who are currently on metoprolol, a pre-conception consultation with healthcare providers is recommended to discuss medication adjustments or alternatives 1.

From the FDA Drug Label

Pregnancy Category C Upon confirming the diagnosis of pregnancy, women should immediately inform the doctor Metoprolol has been shown to increase postimplantation loss and decrease neonatal survival in rats at doses up to 11 times the maximum daily human dose of 450 mg, when based on surface area. There are no adequate and well-controlled studies in pregnant women. The amount of data on the use of metoprolol in pregnant women is limited. The risk to the fetus/mother is unknown Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed.

Metoprolol use in pregnancy is not well established. The FDA drug label indicates that metoprolol should be used during pregnancy only if clearly needed, due to the limited data available and potential risks to the fetus. Key points include:

• Increased postimplantation loss and decreased neonatal survival in rats
• No adequate and well-controlled studies in pregnant women
• Unknown risk to the fetus/mother 2

From the Research

Metoprolol Safety in Pregnancy

• The safety of metoprolol in pregnancy is a topic of interest, with several studies investigating its pharmacokinetics and effects during this period 3.
• A study published in the Journal of Clinical Pharmacology in 2016 found that metoprolol's apparent oral clearance was significantly higher during mid-pregnancy and late pregnancy compared to postpartum, suggesting that dosage adjustments may be necessary to achieve adequate clinical responses 3.
• The same study reported that relative infant exposure to metoprolol through breast milk was less than 1.0% of the maternal weight-adjusted dose, indicating that metoprolol is likely safe for use during lactation 3.
• However, it is essential to note that metoprolol is not explicitly mentioned in the other studies provided, which focus on the safety and efficacy of other antihypertensive agents, such as methyldopa, labetalol, and nifedipine, during pregnancy 4, 5, 6, 7.
• Beta-blockers, a class of medications that includes metoprolol, are generally considered safe for use during pregnancy, although they may cause intrauterine growth retardation if administered during the first trimester 6.

Comparison with Other Antihypertensive Agents

• A systematic review and network meta-analysis published in the American Journal of Obstetrics and Gynecology in 2025 compared the effects of methyldopa, labetalol, and nifedipine on maternal and fetal/neonatal morbidity and mortality, but did not include metoprolol in the analysis 7.
• Another study published in the European Journal of Clinical Pharmacology in 2022 reviewed the pharmacokinetics of methyldopa, labetalol, and nifedipine during pregnancy, but did not mention metoprolol 5.
• A study published in the Lancet in 2019 compared the efficacy and safety of labetalol, nifedipine, and methyldopa for the management of severe hypertension in pregnancy, but did not include metoprolol in the comparison 4.