Until recently, HIV-positive men who want to father a baby with a negative woman have had only one option: sperm washing, a costly lab procedure that separates sperm (which does not carry HIV) from semen (which does). Now positive-negative couples may have a low-risk, lower-cost choice. In July, Pietro Vernazza, MD, of Switzerland, reported that 22 couples had made negative babies the old-fashioned way.
“Having studied HIV transmission through semen for 15 years,” Vernazza says, “[I knew] that the lower the man’s viral load, the lower the risk.” So his team counseled the couples: The men took HIV meds until their viral load stayed undetectable for three months; then their semen was tested for HIV and the women for fertility. When HIV-free semen and female fertility coincided, the women were prescribed one dose of Viread (tenofovir) for pre-exposure prophylaxis and a second to take 24 hours later. Couples then went home to do the deed—without condoms. Seventy percent of the women became pregnant; none got HIV.
But don’t toss the condoms yet. Vernazza estimates the transmission risk as one in 100,000, a conclusion that critics call unsafe. In the August Journal of Acquired Immune Deficiency Syndromes, Brazilian researchers say the Swiss study wasn’t large and diverse enough to offer solid results. And it’s nearly impossible for prevention studies to prove when and how transmission does not occur. Until home testing for seminal viral load is available, conceiving may still require action in the lab as well as the bedroom.