Dupixent During Pregnancy: Is It Safe?

What does the evidence say about dupixent during pregnancy?

1. MotherToBaby's review of two published studies covering 115 and 2,895 pregnancies exposed to Dupixent did not find an increased chance of major birth defects, though a larger study also noted a higher rate of miscarriage whose cause is unclear, since it is hard to separate the effect of the medication from the effect of the underlying condition and other factors. 1
2. Because Dupixent is a large protein molecule, only small amounts are expected to pass into breast milk, and any amount an infant swallows is likely to break down in the baby's stomach and intestines before absorption; published reports of Dupixent use during breastfeeding have not found problems in breastfed infants. 1
3. Dupixent is an IgG4 monoclonal antibody, a molecule type expected to cross the placenta, with transfer described as most pronounced in the second and third trimesters; a systematic review pooling 13 studies and 69 pregnancies found 84.1% ended in live birth, with normal birth weight in 92.3% of cases and no congenital anomalies reported among the babies of mothers using Dupixent for atopic dermatitis. 2
4. A 2025 propensity-matched cohort study compared 293 pregnancies exposed to Dupixent with 293 unexposed pregnancies and found no increased risk of adverse pregnancy outcomes overall, including no significant difference in rates of spontaneous abortion or gestational diabetes. 3
5. A published case followed one woman who continued Dupixent through conception, pregnancy, and breastfeeding; her eczema severity score fell to zero during pregnancy and her infant showed no complications through 48 months of follow-up, illustrating how the drug can support disease control for someone with severe eczema who becomes pregnant. 4

Is dupixent safe in each trimester?

• First trimester. First-trimester exposure is the most common real-world scenario, since many pregnancies aren't confirmed until after a Dupixent dose has already been given, and the picture so far is reassuring but limited. Studies following pregnant women using Dupixent have not shown a clear increase in major birth defects, and this early window is also when placental transfer of large antibody drugs like this one is expected to be lowest. Many people rely on Dupixent to manage significant asthma or eczema, so stopping a biologic that is working, without medical guidance, is not usually advised.
• Second trimester. By the second trimester, more of the antibody drug is expected to reach the fetus as placental transfer of IgG-type antibodies increases. This is also where some of the better controlled data comes from: a 2025 propensity-matched cohort study following 293 pregnancies exposed to Dupixent alongside 293 matched, unexposed pregnancies found no increased risk of adverse pregnancy outcomes overall.
• Third trimester. Placental transfer of Dupixent is expected to be greatest in the second and third trimesters, so a baby delivered late in a pregnancy where Dupixent is being used may have measurable drug levels at birth. Published follow-up, including a case report that tracked one infant for 48 months, has not linked this to developmental problems, but the total evidence base remains small compared with medications that have decades of pregnancy safety data behind them.