Condomless penis-vagina sex can put either partner at risk for transmission of HIV and other sexually transmitted and blood-borne infections (STBBIs) like chlamydia, gonorrhea, hep B, herpes, HPV and syphilis. Evidence indicates that the most common route of HIV transmission is sex.
HIV can transmit penis to vagina or vagina to penis, however there are subtle differences in the rate of transmission. HIV transmission from penis to vagina is significantly higher in comparison to vagina to penis. Penis-anus sex has the highest risk for STBBIs transmission including HIV and Hep C.
There are several effective prevention strategies that helps in reducing transmission of HIV between discordant partners where one of the partner is living with HIV while the other is not. These strategies include the following:
- Undetectable = Untransmittable (U=U): People living with HIV who are adherent to anti HIV medications (anti retroviral therapy or ARTs) and achieve a consistent undetectable viral load, effectively have no risk of transmission of HIV to their partners.
- PrEP: PrEP stands for Pre-Exposure Prophylaxis, and is a tool for HIV negative people who are at risk of HIV infection to reduce their risk of becoming infected. PrEP involves taking anti-HIV medications (antiretrovirals) on a daily basis. When PrEP is taken consistently and correctly, it works to help prevent HIV from replicating within the body’s immune cells, which helps to prevent a permanent infection.
- Other effective ways to reduce the risk of STBBIs are: using condoms (internal / external) and water-based lubrication, engaging in other forms of sex that carry less risk like kissing, oral sex or manual sex (fingering and hand jobs), and engaging in conversation with your partners about routine STBBI testing.