Inclusion Criteria

Concurrent Medication:

Allowed:

• Women - Medications as required for obstetrical management of HIV infection (e.g., acyclovir, ketoconazole, isoniazid, antibiotics, or other antiretroviral therapy if intolerant or failing on AZT), unless specifically excluded.
• Infants - Drug treatment for signs of drug withdrawal (phenobarbital, chlorpromazine, tincture of opium, paregoric or Valium).
• Infants - Medications as indicated for management of an HIV-exposed infant (e.g., hepatitis B vaccine, syphilis treatment, Pneumocystis carinii pneumonia prophylaxis).

Patients must have:

• Documented HIV infection.
• Been receiving AZT during current pregnancy for medical indications.
• Gestational age between 20 and 30 weeks.
• Intention to carry pregnancy to term.
• Available venous access (placement of central line or Hickman catheter not indicated for study purposes).
• Willingness to be followed by a participating site for study duration.

NOTE:

• Father of fetus (if available after a reasonable attempt to contact him) must also provide informed consent.

Exclusion Criteria

Co-existing Condition:

Patients with the following symptoms or conditions are excluded:

• Illness associated with excessive protein loss, e.g., severe proteinuria (protein >= 4 g protein in a 24-hour urine collection).

Patients with the following prior conditions are excluded:

• Evidence of pre-existing fetal anomalies (e.g., anencephaly, renal agenesis, or Potter's syndrome) that may result in a high probability that the fetus-infant would not survive to the end of the study period.
• Chorionic villus sampling (CVS) or percutaneous umbilical blood sampling (PUBS) occurring in this pregnancy prior to study entry.
• Illness associated with excessive protein loss, e.g., chronic diarrhea with no documented weight gain in a 3-month period during pregnancy.
• Pre-existing conditions such as hypogammaglobulinemia or immune thrombocytopenia that are felt to require IVIG therapy.

Prior Medication:

Excluded:

• Receipt of anti-HIV vaccines or passive immunotherapy with HIVIG or IVIG during this pregnancy prior to study entry.
• Receipt of antiretroviral agents other than AZT during this pregnancy prior to study entry (e.g., rCD4, CD4-IgG, d4T, ddC, ddI).