Nearly 9,000 HIV-infected women give birth in the United States each year, which has increased by 30 percent since 2000, according to the Centers for Disease Control and Prevention. Yet the estimated number of babies born with HIV transmitted in utero by their mothers has decreased during the same time period. That’s because more women are taking antiretroviral drugs, which keeps their viral load low and drastically reduces their baby’s risk of getting infected.
Those benefits, however, need to be weighed against a possible increased risk of birth defects associated with the drugs, and a new finding from Harvard School of Public Health provides reassurance for pregnant women with HIV. The study, published online Monday in the journal JAMA Pediatrics, found that most combination of HIV medications taken by pregnant women don’t increase the risk of structural abnormalities in the fetus, such as heart defects, extra fingers or toes, or cleft palates.
The study — one of the largest to date to investigate teratogenic effects associated with HIV drugs — tracked nearly 2600 children born to HIV-infected mothers who took antiretroviral drugs while pregnant and found that nearly 7 percent had some kind of birth defect. While that’s higher than the 3 to 5 percent rate found in the general population, the study researchers believe the difference is due to closer monitoring and recording of minor abnormalities such as a mild skin disorder or a slight defect in the shape of a limb.
“Overall, I think this finding is very reassuring,” said study leader Paige Williams, a senior lecturer on biostatistics and epidemiology at Harvard School of Public Health. “Nothing would suggest that women should avoid treatment early in pregnancy, especially when there’s such a dramatic and demonstrated benefit.”
None of the children in the study were born with HIV, likely because their mothers all took preventive medications.
Williams and her colleagues did find, however, that three of the newer HIV drugs — the protease inhibitors atazanavir sulfate, lopinavir, and ritonavir — were associated with an increased risk of birth defects. Women who took atazanivir sulfate along with other drugs during pregnancy had a nearly 12 percent risk of having a baby with a birth defect compared to 6 percent for those who took other combinations of drugs that didn’t include atazanivir or ritonavir. Those who took ritonavir or lopinavir had about a 9 percent risk.
“This warrants further research, and the drug companies have been evaluating their own safety signals to determine if the increased risk is real,” Williams said. In the meantime, women taking HIV medications should discuss their treatment options with their doctor if they’re planning to become pregnant, she advised. They may want to consider switching to an older drug that’s not associated with increased birth defect risks.