NEW YORK — PrEP has a nasty downside that health advisers feared when it was approved for the U.S. in 2012 — as its use has increased among gay men, so have other sexually transmitted infections (STIs) such as syphilis, gonorrhea and chlamydia, which have all seen spikes in recent years according to an extensive review of multiple PrEP studies published in a recent issue of Clinical Infectious Diseases and reported on by Vox.
The review considered 17 PrEP studies on its use and how sexual behavior has changed. As people began to trust PrEP more over the years, they started having more condomless sex and were worrying less about STIs. The more recent studies showed the strongest escalation, Vox reports.
The authors found that in some studies, PrEP use was associated with a 9 percent increase in the amount of receptive anal sex without a condom with 10 or more partners, an 11 percent increase in the amount of sex without a condom with an HIV-positive person or with someone whose HIV status was unknown, and a 14 percent increase in people never using condoms during anal sex. These are all high-risk behaviors that increase the chances of getting HIV and other STIs, Vox reports.
But they didn’t find any changes in the number of people who had any sex without condoms, partly because so few participants started off using condoms all the time. PrEP didn’t appear to change the number of people who have sex without condoms, Vox reports.