Q. I received steroid shots before my daughter was born to help her lungs. What exactly do the steroid shots do, and is there a optimal time to receive them?
A. Steroid injections are a very commonly used treatment for mothers who are likely to deliver a premature baby. The major benefit is that steroids accelerate maturation of the baby's lungs, and improve the chances that the baby will survive after delivery. Steroid treatment is recommended for all women at risk for preterm birth at 24 to 34 weeks gestation (24 weeks is about 5 1/2 months, 34 weeks is just over 7 1/2 months).
Two kinds of steroids are used: betamethasone (2 shots given 24 hours apart) or dexamethasone (4 shots given 12 hours apart). Only mothers with very serious health problems are not able to receive this treatment. The optimal benefit begins 24 hours after the first injection, and lasts about 7 days. However, if a mother does not deliver within a week of the steroid treatment, most of the available research suggests that subsequent injections of steroids are not helpful.