Partner pregnant? HIV risk doubles

The risk of men being infected by HIV doubles when their partners are pregnant, according to new findings presented today at the M2010 Microbicides: Building Bridges in HIV Prevention conference.

Another important study suggested it was safe for pregnant women to use a small, single dose of a microbicide gel during their pregnancy.

Previous studies on the risk of getting HIV have shown that women are about twice as susceptible to HIV when they are pregnant.

But now Dr Nelly Mugo, from the University of Nairobi and University of Washington, has found the risk is much higher for men too.

“The risk of getting HIV during pregnancy is twofold – both for the pregnant women and for their male partners,” she said.

“Biological factors” are probably driving the increased risk for men, she said.

Women are known to shed more virus when pregnant resulting in a higher HIV concentration in their genital tract.

“We usually call in men during pregnancy for antenatal care for the mom and the baby. Now we need to call in men for their own good to be involved and tested,” Mugo advised.

The study she led involved 3321 serodiscordant couples from South Africa, Botswana, Rwanda, Kenya, Tanzania, Uganda and Zambia.

During the two years of the study 823 pregnancies took place and virus “fingerprinting” showed these transmissions were linked between the partners.

The second small study concerning pregnancy tested the use of a vaginal microbicide – a single small dose tenofovir gel – during pregnancy in 16 healthy HIV-negative women and found it was safe.

“Only small amounts of drug are absorbed into the bloodstream, amniotic fluid and umbilical cord blood,” stated Dr Richard Beigi from the University of Pittsburgh, who led the study for the Microbicide Trials Network (MTN).

The amount absorbed into the maternal blood was 50 to 100 times lower than if the women had taken a tablet orally, and it was 40 times lower in the cord blood level.

Beigi said women had to be on contraception for microbicide trials but not infrequently they fell pregnant during these studies.

“This compelled us at MTN to dive in and start microbicide research during pregnancy,” he said.

“This study is the first to look at microbicide use during pregnancy, and the first time a drug is being tested in parallel (in pregnant and non-pregnant) women.”