The effects of zidovudine on the outcome of pregnancy in HIV-infected women

Objective: In isolated placental cell cultures zidovudine inhibits proliferation of trophoblast cells and their production of hormones. We investigated the effects of zidovudine, taken during pregnancy, on third trimester maternal serum progesterone levels and on neonatal maturity and birth weight. Patients: Eight women who took zidovudine during pregnancy were compared with 28 HIV-infected women who did not receive zidovudine during pregnancy (seropositive controls), and to 11 seronegative pregnant women with risk factors for HIV infection (seronegative controls). Results: The mean (± SD) third-trimester serum progesterone concentration in the study group was 14,200 ± 7,908 ng/dl, which was not significantly different from the mean concentrations in the seropositive controls (15,132 ± 9,692) and in the seronegative controls (13,547 ± 7,244). The three groups had similar mean neonatal birth weights (3,071 ± 352, 3,014 ± 516, and 2,806 ± 450 g, respectively) and neonatal gestational ages (39.25 ± 0.89, 38 ± 2.5, and 38 ± 3.0 weeks, respectively). Conclusion: In this study of a small cohort of HIV-infected pregnant women, no evidence was found to support in vitro data that zidovudine taken during pregnancy might impair the ability of the placenta to support the normal completion of fetal growth and maturation.