1) Prevention of Mother to Child Transmission (PMTCT) programs provide antiretroviral drugs, counseling, and support to pregnant women living with HIV to reduce the risk of transmitting the virus to their babies during pregnancy, childbirth, and breastfeeding. 2) Key interventions include antiretroviral prophylaxis for pregnant and breastfeeding women and their infants, safer delivery and infant feeding practices, and treatment, care and support for women and families. 3) In Tanzania, the national PMTCT program incorporates antiretroviral prophylaxis including various combination drug regimens during antenatal, intrapartum, postpartum, and infant periods, depending on when