Prednisone During Pregnancy: Is It Safe?

What does the evidence say about prednisone during pregnancy?

1. Prednisone and prednisolone pass into breast milk in only small amounts, and among roughly 190 breastfed infants studied, none had reported side effects; waiting about 4 hours after a dose before nursing can lower the baby's exposure even further. 1
2. Older studies suggested a small possible increase in cleft lip or cleft palate with first-trimester prednisone use, but newer studies and a further review of the earlier data do not support that finding; any remaining risk is described as very small, with most exposed pregnancies unaffected. 2
3. A 2014 study included in a broader review of corticosteroid exposure during pregnancy found a non-significant 60 percent increase in the odds of oral clefts among infants exposed to systemic corticosteroids in the first trimester (odds ratio 1.6, 95 percent confidence interval 0.9 to 2.8), a borderline finding that keeps this question open rather than settled. 3
4. The same review concludes there is not sufficient evidence to determine whether corticosteroids like prednisone add to the chance of gestational diabetes, noting that most available studies do not fully separate the medication's effect from the effect of the underlying autoimmune or inflammatory condition being managed. 3
5. In a study of pregnant women with rheumatoid arthritis, a high cumulative oral corticosteroid dose early in pregnancy carried a much greater adjusted risk of preterm birth than no oral corticosteroid use at all (adjusted risk ratio 4.77), and daily doses of 10 mg of prednisone or more later in pregnancy were also linked to a higher rate of early delivery (adjusted hazard ratio 2.45), while lower daily doses showed no clear increase. 4

Is prednisone safe in each trimester?

• First trimester. Older studies raised a possible small increase in cleft lip or palate with first-trimester prednisone use, but newer research, including a 2014 analysis showing a non-significant odds ratio of 1.6, has not confirmed a clear link. Miscarriage risk and the overall chance of birth defects are not expected to rise with typical use. Keep taking prednisone exactly as your prescriber directs rather than adjusting the dose on your own.
• Second trimester. Gestational diabetes sometimes comes up in second-trimester conversations, though a review of the evidence found it is not yet clear whether corticosteroids like prednisone add to that risk beyond the underlying condition itself. Providers generally aim for the lowest dose that keeps your asthma, autoimmune condition, or allergic reaction under control. Routine glucose screening stays part of standard prenatal care either way.
• Third trimester. Longer courses and higher cumulative doses of oral prednisone have been associated with a greater chance of preterm delivery and lower birth weight. One study of pregnant women on corticosteroids for rheumatoid arthritis linked daily doses of 10 mg or more later in pregnancy to a higher rate of early delivery, while lower doses showed no clear increase. It is not fully clear how much of this reflects the medication versus the severity of the condition being managed, so loop in your obstetric team about your dose and timeline heading into delivery.