HIV-positive women who are pregnant and have a fully suppressed virus thanks to antiretroviral (ARV) treatment may have a small risk of experiencing a detectable viral load, otherwise known as a viral rebound, close to delivery, aidsmap reports.

Publishing their findings in Obstetrics and Gynecology, researchers analyzed data about a group of women in the British Columbia Perinatal Database for HIV-positive women, covering 1997 to 2015. They selected women who experienced a live birth who took ARVs for at least four weeks during their pregnancy and who had at least one fully suppressed viral load test result during their pregnancy. Between 1997 and 1998, a fully suppressed virus meant a viral load of less than 400; after then, it meant less than 50.

The researchers defined a viral rebound as at least one viral load test result above the aforementioned thresholds within 31 days prior to delivery or a viral load test result within 72 hours after delivery if there was no test result from the month before delivery.

A total of 318 women were included in the analysis. Nineteen women (6 percent) experienced a viral rebound during pregnancy. Thirteen of these women experienced viral rebounds between 50 and 1,000, while four experienced rebounds between 1,001 and 10,000 and two experienced rebounds between 10,001 and 16,000. The median length of time between the last viral load test showing an unsuppressed viral load and delivery was one day.

The women were more likely to experience a viral rebound if they were Aboriginal, had hepatitis C virus (HCV) and used cocaine. The study is limited by the fact that the findings may not be generalizable to other populations of pregnant women, in particular because of a high rate of substance use among the British Columbia population.

To read the MedPage Today article, click here.

To read the study abstract, click here.