Pregnancy

The safety of tenofovir (Viread) in pregnant women has not been demonstrated, but one study of tenofovir in pregnant monkeys found some evidence that infant size, weight, and bone porosity were reduced in infants exposed to tenofovir. Circulating levels of insulin-like growth factor were also significantly lower in the exposed infants.¹

An analysis of data submitted to the Antiretroviral Pregnancy Registry found no indication that tenofovir (Viread) use by HIV-positive pregnant women, either during the first trimester or later in pregnancy, was associated with an increased risk of birth defects. The registry collects reports from healthcare providers worldwide about adverse outcomes amongst infants born to women taking anti-HIV drugs during pregnancy. Tenofovir use was found in approximately 10% of the roughly 10,000 cases for which there was adequate outcomes information. The majority of women had asymptomatic HIV disease, but about 20% had serious immune deficiency.

In the US, the overall rate of birth defects is 2.7%, the same percentage that was found in infants exposed to antiretroviral drugs during gestation. Looking specifically at tenofovir, birth defects were found in 2.3% of infants exposed to any tenofovir-containing regimen during the first trimester and in 1.5% exposed during the second or third trimester. None of the five infants born to women who had used the fixed-dose combination of tenofovir, efavirenz, and emtricitabine (the three drugs in Atripla) had any abnormalities. Further, no congenital abnormalities were reported amongst women taking tenofovir who had induced abortions, miscarriages, or stillbirths, indicating that the drug did not cause problems leading to early pregnancy loss.²