Pregnancy ups HIV risk in negative partner

(Kim Ruoff)

Research presented at the M2010, the 6th biennial International Microbicides Conference in Pittsburgh, on May 23 detailed a novel study that has found HIV transmission from a pregnant positive partner increases two-fold in HIV negative men.

For decades public health professionals and researchers have been battling HIV and studying the links between mother-to-child transmission (MTCT) and ways to empower females to practice safe sex due to the prevalence of male-to-female transmission.

Strides have been made but the rate of treatment is dwarfed by transmission, 2:5 according to Microbicide Trial Network's (MTN) analysis of 2007 data from UNAIDS and the US Center for Disease Control (CDC). "In sub-Saharan Africa women aged 15-24 are the highest risk group Globally, women account for half of all HIV infections, and in sub-Saharan Africa, women comprise 60 percent of all infected adults," and in "southern Africa women aged 15 to 24 are at least three times more likely than their male peers to be infected with HIV."

According to Nelly Mugo, MD, MPH, a research scientist at the University of Washington, University of Nairobi/ Kenyatta National Hospital (KNH) and East African director of the Partners in Prevention HSV/HIV Transmission Study, Pre-Exposure Prophylaxis (PrEP), pregnant female-to-male transmission is something that needs greater attention as "biological changes that occur during pregnancy may make women more infectious than they would be otherwise."

The research took place in Botswana, Kenya, Rwanda, South Africa, Tanzania, Uganda and Zambia where 3,321 couples (1,085 couples included a positive male and 2,236 couples where the female was positive) were monitored for two years producing 823 pregnancies.

The study concluded "pregnancy was associated with increased risk of both female-to-male and male-to-female HIV transmission" and "...the link between pregnancy and HIV risk was much clearer (in men), even after considering whether or not they had engaged in unprotected sex or were circumcised. Measures of viral load and CD4 counts of the infected partner also had no bearing."

The authors cautioned that much more researcher is needed and noted, "for women with an HIV- infected partner, the study found that factors other than pregnancy also likely contributed to this increased risk, such as sexual behavior."

Nonetheless, "increased female-to-male transmission of HIV during pregnancy may be due to physiological and immunological changes that occur with pregnancy."

For more information on M2010, go to: http://www.microbicides2010.org