Migraine Antibodies Tied to Increased Miscarriage Risk in Pregnancy Study
A retrospective U.S. study of 7,100 pregnant migraine patients found that early exposure to anti-CGRP monoclonal antibodies was associated with a 42% higher risk of spontaneous abortion. Propranolol use did not show the same association. The researchers said their findings support guidelines to stop anti-CGRP drugs at least 5 months before conception and switch to established preventive treatments.
The study drew on U.S. commercial claims from 2018-2021, following 7,119 women with migraine before pregnancy and 7,579 singleton pregnancies. It compared early pregnancy exposure to four anti-CGRP antibodies—erenumab, fremanezumab, galcanezumab, eptinezumab—or propranolol against no exposure.
CGRP helps regulate blood vessels and is thought to matter for implantation and placental blood flow. Because these antibodies persist about a month, guidance advises stopping them five to six months before conception.
The findings may prompt clinicians to revisit migraine prevention plans for patients who could become pregnant, potentially shifting care toward older options such as propranolol. For patients and families, clearer preconception counseling could reduce uncertainty, though retrospective data cannot prove cause and effect. Insurance coverage and treatment access may also be affected if guidelines are reinforced.