Pre-exposure prophylaxis for HIV during pregnancy did not harm the fetus
A systematic review and meta-analysis showed that pre-exposure prophylaxis for HIV infection during pregnancy did not increase the risk of perinatal adverse outcomes. Oral medications used for such prophylaxis did not increase the risk of preterm labor, low birth weight, or neonatal death. The results of the analysis are published in the journal eClinicalMedicine.
During pregnancy and the postpartum period, the risk of HIV infection in women in countries with a high prevalence of the virus (such as Africa or Russia, where nearly 859,000 cases were registered in 2022 according to Rosstat) more than doubles. Moreover, it is estimated that about one-third of cases of vertical transmission of HIV, i.e. from mother to child, in these settings occur as a result of the mother's seroconversion during pregnancy, when HIV antibodies are not detected in the blood. Meanwhile, untreated HIV infection in the mother is associated with an increased risk of adverse perinatal outcomes such as preterm birth, low birth weight, intrauterine developmental delay and stillbirth.
However, antiretroviral therapy may also increase the risk of perinatal complications. The World Health Organization recommends daily tenofovir-based tablets, a vaginal ring with dapivirine, or intramuscular cabotegravir as part of combination HIV pre-exposure prophylaxis (PrEP or PrEP) strategies. However, data on the safety of PrEP used during pregnancy are limited because investigational drugs are usually withdrawn for participants who become pregnant during the course of the studies. It is thought that the use of PrEP among HIV-negative pregnant women in populations with high HIV prevalence may reduce maternal HIV incidence and vertical transmission.
A research team led by Joris Hemelaar at the University of Oxford conducted a systematic review and meta-analysis of 13 studies (eight randomized controlled trials and five cohort studies) with a total sample of 8,712 pregnant women in Africa. In a meta-analysis of six randomized controlled trials that included 1,047 women, researchers found no association between DCP and preterm birth compared to no DCP. A meta-analysis of cohort studies showed similar results. In addition, a confounding-adjusted analysis of three cohort studies showed a statistically significant lower risk of preterm birth with BFD compared with no BFD.
Researchers found no evidence of an association between DKP and low birth weight, but a meta-analysis of two unadjusted cohort studies (4,989 women) found a statistically significant higher risk of intrauterine developmental delay (small for gestational age fetus). No such association was observed in the adjusted cohort study. There was no association between DCP and stillbirth. Evaluation of the association of dapivirine ring with preterm labor also showed no statistically significant increase in risk.
Researchers recognize that the reliability of these findings is low because of the limited data available and the poor quality of the studies: most of them are more likely to lack evidence of harm than evidence of no harm. However, even these results can be considered encouraging and supportive of the World Health Organization's recommendations on PrEP during pregnancy.