Recommendations regarding HIV screening and treatment of pregnant women and prophylaxis for perinatal HIV transmission have evolved considerably in the United States over the last 25 years, reflecting changes in the epidemic and the science of prevention . Treatment of HIV disease in general and during pregnancy has progressed with an increasing proportion of women receiving combination antiretroviral therapy or triple antiretroviral drug prophylaxis throughout pregnancy. With the implementation of recommendations for universal prenatal HIV counseling and testing, antiretroviral prophylaxis, scheduled cesarean delivery, and avoidance of breastfeeding, the rate of perinatal HIV transmission has dramatically diminished to less than 2% in the United States and Europe.