<qa>  What is the name of the study drug that women will be randomized to receive?Women will be enrolled between 28 and 38 weeks of gestation. As part of normal PMTCT services, they may choose NVP-boosted ZDV or single dose NVP for PMTCT; We anticipate that most 80 will choose the former. At arrival for delivery, they will be randomized to receive either the two study drugs intervention or no drug control. A total of 400 women will be randomized, and followed, along with their infants, for 6 months. 