Read Full Story Paige Williams, senior lecturer on biostatistics at Harvard T.H. Chan School of Public Health, studies the health and development of children whose HIV-infected mothers took antiretroviral (ARV) drugs during pregnancy. In a study published last year, you found that the overall risk of birth defects was low for women taking ARVs during early pregnancy — in keeping with previous research that has found ARV use in pregnancy to be generally safe. What did you look at in the current study, and what did you find?The current study focuses on health and developmental problems that might emerge later in life, such as cognitive, hearing, and language impairments, and metabolic problems. We found that taking combination antiretroviral drugs during pregnancy does not increase the overall risk of these adverse outcomes in babies born to mothers living with HIV.However, one commonly used drug called zidovudine (or AZT) was linked to about 70% higher risk for metabolic problems in these children. We did not anticipate finding this, since this drug has not previously been linked to metabolic problems. In contrast, many drugs in the class of ARVs known as protease inhibitors were linked to lower risk of metabolic problems in this study, even though this drug class has often been linked to higher risk of issues such as elevated cholesterol.