Efficacy of Nevirapine Compared to ZDV + 3TC Administered in Labor and Again at Postdelivery in HIV Positive Women

Inclusion Criteria: * Pregnant women who present after 38 weeks gestation or in labour after 35 weeks gestation who are tested HIV positive. Estimated gestational age will be determined by one or more of the following: * Reliable menstrual history, which corresponds with uterine size * Physical examination * Estimated fetal weight * A consent form for the mother and neonate will be signed by either the mother or the guardian prior to inclusion Exclusion Criteria: * Mothers who have taken any antiretrovirals in the last 12 months * Mothers who are not able to take oral medication * Mothers who present with ARDS (acute respiratory distress syndrome), septic shock or eclampsia * Mothers presenting in discomfort, i.e. regular painful uterine contractions, or other factors that may contribute to her not being able to understand and sign the informed consent for HIV testing and study participation * Use of another investigational drug or concurrent participation in another investigational protocol during the current pregnancy * Unwillingness or inability to reasonably comply with the protocol (i.e., mother and neonate/infant could not be followed for the full 6 weeks of the trial) * Grade 4 SGPT (Serum glutamate pyruvate transaminase) (\>10 times the upper limit of normal value), if known prior to delivery * A recent history (6 months preceding the study) or current evidence of drug abuse and/or alcoholism * Mothers with fetuses with anomalies incompatible with life, if known prior to delivery * Decision to deliver the infant by elective Cesarean section * Amniocentesis was indicated * Infants with severe growth retardation diagnosed before birth Infants who fall into the following groups will not receive treatment, but the mother-infant pair will remain in the trial * Infants with malformations incompatible with life * Life-threatening perinatal conditions which do not allow oral therapy (e.g., sepsis)