Pre-exposure prophylaxis, or PrEP, is safe for pregnant women to use, according to new research presented at the HIV Research for Prevention (HIVR4P2018) conference in Madrid, Spain.
According the study, which evaluated pregnant women and infants in Kenya, babies born to women who took PrEP were no more likely to be underweight, to be born prematurely, or to have birth defects compared with babies born to women who did not take PrEP.
Though World Health Organization (WHO) guidelines already recommend PrEP for high-risk pregnant women, this data should further reassure clinicians that it's safe to prescribe PrEP for any women who need it regardless of their pregnancy status, according to the study's lead author, Julia Dettinger, M.P.H., research scientist, University of Washington, Seattle.
Compounding the need for better PrEP access in pregnant women is a recent meta-analysis finding that a woman's risk of acquiring HIV triples during late-stage pregnancy and during the weeks after birth.
The data Dettinger presented in Madrid is a larger-scale study on the safety of PrEP in pregnant women. Dettinger and her colleagues analyzed data collected during the PrEP Implementation for Young Women and Adolescents (PrIYA) Program, which looks into challenges implementing PrEP among women in Kisumu County in Kenya.
"Over the course of about a year, PrIYA has screened almost 25,000 women for HIV risk factors and initiated about 4,000 of those women on PrEP," Dettinger said. "From that evaluation, we identified 4,434 women who had no PrEP exposure during pregnancy and 246 women who reported using PrEP in pregnancy."
Of these women, about 12% started PrEP during the first trimester, 48% during the second trimester, and 39% during the third trimester. About 10% of the women only used PrEP for a week or so, while 28% used it for more than one week but less than one month. The largest portion of women -- 40% -- used PrEP for one to three months, and 12% used it for over three months.
Related: New Study Shows Women's HIV Risk Triples During Pregnancy, Quadruples Postpartum
These women's babies were no less healthy than babies born to women who didn't use PrEP. Both arms of the study saw babies born at about the same gestational age: 38 to 40 weeks. There were more preterm births in the non-PrEP arm (5.3% compared with 2.5%). Meanwhile, birth weight, birth length, and size relative to gestational age were about the same in both groups. As well, both arms had exactly the same rate of birth defects (0.4%).
"What we basically found," said Dettinger, is that "there were no statistically significant differences between the PrEP-exposed and unexposed infants."
Reassuringly, the finding is in-line with WHO and Centers for Disease Control and Prevention guidance, as well as data from smaller studies and from HIV-positive mothers taking "tenofovir disoproxil fumarate (TDF)-based regimes -based regimens.
Though guidelines recommend PrEP initiation in high-risk groups, not everyone is convinced that PrEP is safe to use in pregnant women. Dettinger hopes that her research is used to reassure clinicians that PrEP can and should be prescribed to at-risk pregnant women.
"We found a lot of women who were really excited about PrEP and either knew their partner was [HIV] positive or knew they couldn't have that partnership status conversation," she said. Even so, for these women, an official endorsement from groups such as WHO and the Kenyan Health Ministry "isn't particularly reassuring."
"We're hoping that we're able to feed this information back to our nurses and the folks who are doing the PrEP counseling to say that more evidence is coming out, [and] it's still looking safe," she said.