The Safety and Effectiveness of Zidovudine in HIV-Infected Pregnant Women and Their Infants

Inclusion Criteria Concurrent Medication: Allowed for infants: * Treatment for signs of drug withdrawal (e.g., phenobarbital, chlorpromazine, tincture of opium, paregoric, or Valium). * Treatment for nonserious conditions (e.g., syphilis treatment, hepatitis B vaccine). * All essential supportive treatment for conditions that are nonlife threatening as deemed by the on-site pediatrician. * Acetaminophen. * Standard immunizations. * Allowed for women: * All medications/treatments as required for normal OB care of HIV+ women, except as noted under exclusions. * Pneumocystis prophylaxis as indicated. * Topical steroids. Parenteral and oral steroids for 6 or fewer days. Concurrent Treatment: Allowed for pregnant woman: Blood transfusion for anemia (hemoglobin less than 7 g/dl). Allowed for infant: \- Blood transfusions for anemia except if attributed to study drug. \- Patients must: * Have HIV infection. * Intend to carry pregnancy to term. * Be willing to be followed by a participating ACTG center for duration of the study. * Be able to provide informed consent (if available, father of the fetus must also provide informed consent). * Infants may enroll simultaneously in other pediatric protocols after completing the initial 6 weeks of study treatment. * Inclusion age for women is 13 years old or more or IRB local age of consent. * Inclusion age for infants is 0 to 20 months. Exclusion Criteria Co-existing Condition: Infants with the following conditions or symptoms are excluded: * Requiring treatment for hyperbilirubinemia (except phototherapy). Concurrent Medication: Excluded: * Infants: * Antiretroviral drugs or vaccines. * Excluded during current pregnancy: * Zidovudine (AZT). * Other antiretroviral agents (e.g., rCD4, CD4-IgG, d4T, didanosine (ddI), dideoxycytidine (ddC)), passive immunotherapy (e.g., HIVIG), anti-HIV vaccines, cytolytic chemotherapeutic agents. * Corticosteroids for equal to or more than 7 days. Patients with the following are excluded: * Evidence of preexisting fetal anomalies that may (1) result in a high probability that the fetus/infant will not survive to the end of the study period (e.g., anencephaly, renal agenesis, or Potter's syndrome); or (2) increase the fetal tissue concentration of zidovudine (AZT) or its metabolites to a toxic level (e.g., neural tube or ventral wall defects). * Baseline sonogram completed within 28 days prior to randomization that demonstrates 2nd trimester findings of anencephaly or oligohydramnios, or 3rd trimester findings of unexplained polyhydramnios, fetal hydrops, ascites or other evidence of preexisting in-utero anemia. * History of intolerance to AZT dose of 500 or less mg/day prior to this pregnancy that resulted in discontinuation of treatment for more than 4 weeks. * Recipient of AZT during current pregnancy for any indication or meet criteria for AZT as defined by this protocol (CD4+ cell counts less than 200 cells/mm3 or AIDS). * Infants not having parent/guardian available to give informed consent if necessary. Prior Treatment: Excluded during current pregnancy: * Radiation therapy.