Association between HIV in pregnancy and antiretroviral therapy, including protease inhibitors and low birth weight infants.

OBJECTIVE To determine the incidence of low birth weight infants born to HIV seropositive women and to demonstrate any effects of antiretroviral therapy on birth weight. METHODS Retrospective review of all obstetrical medical records from January 1, 1995 through June 30, 1998 to identify HIV seropositive women. We evaluated their antiretroviral therapy, CD4 counts, and birth weights of their newborns. We conducted detailed review of the clinical and laboratory findings for the HIV-infected untreated patients, women who received ZDV antepartum alone, and those who received PIs as part of antiretroviral treatment. RESULTS The frequency of low birth weight infants was significantly increased in HIV seropositive compared to HIV seronegative parturients. Low birth weight infants were more frequent among HIV infected women with lower CD4 counts but the association was not statistically significant. Women who received no antepartum treatment, antepartum only ZDV, and those treated with PIs had significantly more low birth weight infants than did comparison groups. HIV seropositive women also had high frequencies of several obstetrical risk factors for low birth weight infants. CONCLUSION The present study showed a significantly increased frequency of low birth weight infants among HIV infected women and especially the subgroups of infected women who received no antepartum treatment, antepartum ZDV only, and those treated with PIs. This association, however, may be related to the presence of many other preterm obstetrical risk factors noted in this study. Increasing numbers of HIV seropositive women are being treated with PIs according to the Centers for Disease Control (CDC) guidelines. If PIs are a cause of low birth weight infants, women taking these drugs may have incremental risk of low birth weight.