First Trimester Exposure to Antiretroviral Therapy and Risk of Birth Defects

Background: Use of antiretroviral (ARV) drugs during pregnancy has been associated with an increased risk of birth defects, but the evidence remains inconclusive. Methods: We identified infants born to human immunodeficiency virus (HIV)-infected mothers between 1994 and 2009 using Tennessee Medicaid data linked to vital records. Maternal HIV status was based on diagnosis codes, prescriptions for ARVs and HIV-related laboratory testing. ARV exposure was identified from pharmacy claims. Birth defects diagnoses during the first year of life were identified from maternal and infant claims and vital records and were confirmed through medical record review. Multivariate logistic regression models were used to evaluate associations between first trimester ARV dispensing and birth defects. Results: Of 806 infants included in the study, 32 (4.0%) had at least 1 major birth defect, most (44%) in the cardiac system. There was no increased risk for infants exposed in the first trimester to ARVs compared with unexposed infants (odds ratio = 1.07; 95% confidence interval: 0.50-2.31). Of the 20 infants exposed to efavirenz, none had a birth defect (0%; 95% confidence interval: 0.0-13.2). Conclusions: There was no significant association between first trimester ARV dispensing and the risk of birth defects in this Medicaid cohort of HIV-positive women.