Melbourne, Aug 6 : Heterosexual couples are at a greater risk of transmitting the HIV virus during sex than most people realise, according to a new study.
It is said that on average only one heterosexual transmission of the AIDS virus would be expected for every 1000 sexual contacts, assuming one partner was HIV-positive and the other negative.
However, American researchers claim that the actual figure could be as high as one transmission for every 10 instances of vaginal sex, reports News.com.au.
At International AIDS Conference, researchers said that the risk could be as high as one transmission for every three instances of heterosexual anal sex.
After reviewing 27 previous studies on HIV transmission, the team concluded that underestimate had arisen because most of the studies were based on heterosexual couples with particularly low-risk habits.
The findings were published online by The Lancet Infectious Diseases.