To assess the use of antenatal corticosteroids in clinical circumstances for which both the NIH Guideline and local experts recommend their use and to describe characteristics associated with failure to use recommended antenatal steroids. We convened local experts to adapt the NIH statement by identifying clinical circumstances for which they agree antenatal steroids should always be used. We conducted a retrospective chart review on a cohort study of mothers who delivered premature (24-34 weeks) infants between 2000 and 2002 at three New York City hospitals and investigated the association of failure to treat with antenatal steroids with characteristics of the mother, pregnancy, delivery, and hospital. Twenty percent (101/515) of eligible mothers failed to receive indicated antenatal corticosteroid therapy. Of these, 43% delivered more than 2 h after admission, and 33% delivered more than 4 h after admission, indicating sufficient time to have treated them. Lack of prenatal care, longer gestation, advanced cervical exam, and intact membranes at admission were associated with failure to receive the recommended therapy. Antenatal steroids were under-utilized in our sample. If our results our generalizable, opportunities for quality improvement in the antenatal management of mothers in preterm labor exist.