OBJECTIVE: To determine the impact of anti-asthmatic medications on pregnancy outcomes in the Georgia Medicaid population. METHOD: Using Medicaid claims data from Georgia, we examined pregnancy outcomes over six months from January to June 1997. Medication and medical history twelve months prior to each eligible outcome were examined. Abnormal pregnancy outcomes included: spontaneous abortion, hemorrhage, pre-term infant and stillborn infants. Logistic regression model included pregnancy outcome as the dependent variable. The independent variables included age, race, medicaid eligibility, diagnosis for asthma, anti-asthmatic medication, epilepsy, diabetes, AIDS, anemia, alcohol abuse, drug abuse, psychosis, depression, tobacco abuse, bipolar disorders and obesity. RESULTS: There were 6,396 eligible women who had a pregnancy outcome in the six-month study period. Logistic regression analysis indicated that consumption of prescription drugs for asthma and other pulmonary conditions increased the risk of an abnormal outcome by 36%. Comorbidities like depression and obesity increased the risk of an abnormal outcome by 50% and 90% respectively. Age of 35 or older, had an 89% increase in abnormal outcomes. CONCLUSIONS: We showed that women in the Georgia Medicaid program had an increased risk of an abnormal pregnancy outcome when using anti-asthmatic medications during pregnancy. This research has further substantiated the possible teratogenic effect hypothesis of anti-asthmatic medications in pregnancy. Larger cohorts of women need to be studied over a longer period of time to fully explore this teratogenic relationship. Results may have implications for more judicious use of such medications during pregnancy and for careful pre-natal care for such women.