Benzodiazepines in Pregnancy

What did the new benzodiazepine pregnancy study find?

The research, published in Annals of Internal Medicine on October 13, examined Medicaid and commercial insurance records covering approximately 4.2 million pregnancies. Nearly 79,000 involved a benzodiazepine prescription filled during the first trimester. The American College of Physicians described the overall findings as reassuring for early pregnancy exposure. [ACP research announcement](https://www.newswise.com/articles/benzodiazepine-use-in-first-trimester-not-associated-with-higher-risk-for-major-birth-defects)

After adjustment for measured differences between groups, major malformation risks were 4.0% with exposure versus 4.1% without exposure in Medicaid, and 4.9% versus 4.8% in commercial insurance. The pooled adjusted relative risk was 0.99, with a 95% confidence interval of 0.96–1.03: an estimate close to no difference. These percentages describe all identified major malformations, not defects proven to have been caused by medication. [Original study](https://pubmed.ncbi.nlm.nih.gov/42863122/)

Why does this study not settle every pregnancy safety question?

This was an observational study, so adjustment cannot eliminate every difference between people who did and did not receive medication. Filling a prescription also does not establish exactly how much medication someone took. Because the analysis concerned live-born infants and malformations present at birth, it cannot settle questions about miscarriage or later childhood development. [Study methods and limitations](https://pubmed.ncbi.nlm.nih.gov/42863122/)

Earlier evidence was less reassuring. A 2022 PLOS Medicine study of approximately 3.1 million pregnancies in South Korea found small increases in overall malformations and heart defects after adjustment, with stronger associations at higher doses. It also had limitations, including possible exposure misclassification and residual confounding. Differences in populations, prescribing, outcome detection and follow-up could contribute to differing results; that is a methodological possibility, not an established explanation. The newer findings should therefore be considered alongside the earlier evidence. [South Korean cohort study](https://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.1003945)

How should this evidence inform treatment during pregnancy?

The American College of Obstetricians and Gynecologists' 2023 guideline recommends limiting benzodiazepine prescribing for anxiety during pregnancy and postpartum. It identifies selective serotonin reuptake inhibitors as the preferred initial medication approach and recognizes a role for psychotherapy. Benzodiazepines may sometimes provide temporary relief while another treatment takes effect, or have a role when initial treatments fail. Reassuring birth-defect evidence does not by itself determine which treatment best meets an individual's needs. [ACOG Clinical Practice Guideline No. 5](https://ilpqc.org/wp-content/uploads/2025/05/Treatment-and-Management-of-Mental-Health-Conditions-During-Pregnancy-and-Postpartum_ACOG-Clinical-Practice-Guideline-No.-5.pdf)

People taking benzodiazepines regularly should not stop abruptly after discovering a pregnancy. The FDA warns that sudden discontinuation or rapid dose reduction can cause severe withdrawal, including seizures; any taper needs an individualized plan. [FDA benzodiazepine safety communication](https://www.fda.gov/drugs/drug-safety-and-availability/fda-requiring-boxed-warning-updated-improve-safe-use-benzodiazepine-drug-class)

Timing also matters. MotherToBaby explains that lorazepam exposure during pregnancy can cause temporary newborn symptoms, including jitteriness, muscle weakness or breathing difficulties, although not every exposed baby is affected. These outcomes are distinct from structural birth defects. Discussing continued use with maternity and prescribing teams allows treatment and newborn care to be planned together. [MotherToBaby lorazepam fact sheet](https://mothertobaby.org/fact-sheets/lorazepam/)