SUMMARY Concerns have been raised regarding the use of repeated courses of systemic glucocorticosteroids given to pregnant women with threatened premature labour to improve fetal lung maturity. Most worrying are animal studies showing detrimental effects on the developing brain, though human data to date are conflicting. Additional concerns relate to the fetal origins of adult diseases, particularly vascular diseases such as hypertension and atherosclerosis. It is currently recommended that obstetricians give only a single course of antenatal corticosteroids to pregnant women to enhance lung maturity instead of giving repeated doses, which was previously a common practice. Other clinicians including dermatologists, gastroenterologists and rheumatologists may have reason to provide systemic glucocorticosteroids to pregnant women. Although systemic glucocorticosteroids all cross the placenta to some degree, the extent to which they do so depends on the drug involved. The choice of systemic glucocorticosteroid for the pregnant women in light of this evolving literature is discussed.