Although a complete discussion of the therapy for the pregnant HIV-infected patient is beyond the scope of this section, it is worth highlighting several important issues. First, it is generally accepted that women should receive optimal therapy for their HIV whether or not they are pregnant. At the same time, consideration has to be given to the potential effects of the drugs used on the fetus as well as the effects on the perinatal transmission of HIV. HIV can be transmitted from the mother to the child in utero, at the time of birth, or through breast-feeding. Breast-feeding should thus be avoided in such patients.

Moreover, it has been shown quite clearly in a randomized, double-blind clinical trial that the risk of perinatal HIV transmission can be substantially reduced by the administration of zidovudine orally to the mother after the first 14 weeks of gestation, intravenously during the intrapartum period, and to the newborn during the first 6 weeks of life. This has only been shown with zidovudine, and for this reason zidovudine should be included in the treatment regimen of the mother whenever possible and the intrapartum and neonatal zidovudine components of this treatment regimen should be administered to reduce the risk of perinatal transmission.

With regard to the treatment of the mother, zidovudine is the only drug that has been extensively studied in pregnancy, and there are only limited data on the pharmacokinetics and safety of the other agents. Many of the drugs now used for the treatment of HIV turn up positive on at least one of the in vitro and animal screening tests for the effects of drugs on the fetus, and even zidovudine has been shown to induce tumors in mice exposed to very high doses in utero.

Even so, there is at least some experience in the use of these drugs in pregnancy, and most members of the DHHS-Kaiser panel recommended continuing or (for mothers who were not on therapy) initiating optimal therapy regardless of the gestational age of the fetus. With regard to the PI, there are some theoretical concerns regarding the use of indinavir late in pregnancy. The hyperbilirubinemia and the renal stones that can be associated with the use of this drug could be particularly problematic in newborns if substantial transplacental passage of this agent occurs; and for this reason, this drug might best be avoided just before the time of delivery.

Health care providers who treat HIV-infected pregnant women are strongly encouraged to report cases of perinatal exposure to these drugs to the Antiretroviral Pregnancy Registry, which is a collaborative project of the National Institutes of Health, the Centers for Disease Control and Prevention, and staff from various pharmaceutical manufacturers.