Background and Purpose The safety of antiretroviral therapy for the fetus is important for women with chronic hepatitis B (CHB) infection who are on long-term treatment and who want to become pregnant. To this end we analyzed neonatal safety data from the US Antiretroviral Drug Pregnancy Registry, the largest database of antiretroviral drugs for HIV and chronic hepatitis B during pregnancy.
Methods Data were obtained from cases registered in the US Antiretroviral Drug Pregnancy Registry from 1989 to 2011. The primary outcome was the incidence of major birth defects for exposure to all antivirals, single classes of drugs, and individual drugs compared with a population-wide controlled study. Of the cases concerning chronic hepatitis B, only lamivudine (LAM) and tenofovir (TDF) had sufficient personal data for review (200 cases).
Results Among the 13711 cases analyzed, the total birth defect incidence (2.8%, 95% confidence interval 2.6C3.1%) was compared with the CDC (CDC) population-based survey data (2.72%, 2.68C2.76%, p=0.87) and two prospective cohort studies of neonatal antiretrovirals (2.8%, 2.5C3.2%, p=0.90 and 1.5%, 1.1C2.0%, p<0.001) were similar. The incidence of birth defects was similar for early and mid-late gestation exposures (3.0% and 2.7%). No increased risk of major birth defects was found with lamivudine or tenofovir compared with the full population control study. No specific mechanism for major birth defects was identified for antivirals alone or as a whole. Conclusions No increased risk of major birth defects was found with all or lamivudine or tenofovir for women taking antiviral drugs associated with the treatment of chronic hepatitis B during pregnancy compared with a population-wide controlled study. Follow-up reports on the safety and efficacy of antiviral drugs in pregnancy are necessary to inform patients of the risks and benefits during pregnancy.