Last month, the connection between body-hair removal and sexually transmitted diseases (STDs) once again gave rise to a flurry of headlines. Media had previously reported on “studies” purporting that the popularity of waxing is leading to the extinction of pubic lice, or that shaving increases risk for a little-known STD called molluscum contagiosum.
The idea that waxing one’s nether regions is tantamount to habitat destruction for the lowly pubic louse makes a certain amount of sense. But was it really true that waxing was leading to diminished pubic-lice populations, or just a case of the media blowing an obscure medical factoid out of proportion? Ditto with the claims about molluscum contagiosum — though they were based on perfectly plausible premises, having to do with shaving causing microscopic skin injuries that create openings for infectious viruses, the average reader might not have been able to rely on a journalist’s ability to translate a scientific article from “medical-ese” into an easy-to-understand, yet fully nuanced, magazine blurb.
The case isn’t closed on the link between body-hair removal and STDs.
As we’ve written before, the reporting in the popular media left out important details — such as the fact that these weren’t studies at all, but rather educated guesses based on observations, published as letters to the editor. No one was comparing pubic lice infestations or sexually transmitted infections between groups of people with and without pubic hair.
The medical journal Sexually Transmitted Infections recently published a study based on a survey of 7,470 American adults who had had at least one sexual partner. The salient point the media pounced on was that removing pubic hair increases STD risk by 400 percent: NPR screamed that “Going Bare Down There May Boost The Risk Of STDs,” Time proclaimed “Grooming is linked to a higher risk of STIs,” and The Guardian spooked readers with a rather tasteless piece about “the health dangers of bikini waxing.” Even Saturday Night Live’s Weekend Update got in on the action, albeit with a crude joke about old men’s genitals.
But let’s leave headlines behind and delve right into the medical journal itself. After controlling for age and number of lifetime sexual partners, the investigators analyzed frequency of hair removal in relation to risk for cutaneous STDs, secretory STDs, and pubic lice. “Cutaneous” STDs, i.e., herpes, HPV, syphilis, and molluscum contagiosum, are transmitted by skin-to-skin contact. Risk is thought to be heightened when pubic hair is shaved, as razors cause microscopic injuries through which bacteria and viruses can more easily invade the body. “Secretory” STDs — gonorrhea, chlamydia, and HIV — are transmitted by semen and vaginal fluids, and risk shouldn’t be affected by the presence or absence of body hair.
The findings? Compared to those who have never removed their pubic hair, people who remove all pubic hair at least 12 times a year are 4.4 times more likely to have had a cutaneous STD, and more than twice as likely to have had a secretory STD. People who trim their hair daily or weekly are 3.6 times more likely to have had a cutaneous STD, and 1.6 times more likely to have had a secretory STD. (Neither group is at a significantly higher or lower risk for pubic lice.)
Does that mean body-hair removal definitely raises STD risk? Not so fast.
While the article published last month was an actual scientific study, in which “non-groomers” were compared to “groomers,” it was still just a starting point, with several weaknesses that future research must overcome. On NPR, co-author Benjamin Breyer admitted as much: “Right now, we have no way [of] knowing if grooming causes the increase in risk for infections. All we can say is that they’re correlated.”
You may have heard the phrase “correlation does not equal causation.” It’s a reminder that we can’t always assume two events are related, no matter how much it might seem that way. It’s possible that groomers are more likely to engage in high-risk sexual activities — in fact, the finding that groomers were more likely to have a history of secretory STDs, which aren’t transmitted by skin-to-skin contact, hints that there could be more differences between non-groomers and groomers than the mere presence or absence of pubic hair. There are other factors that might affect one’s STD status, such as condom use or previous HPV vaccination, that the authors did not examine. Finally, the study didn’t establish which came first — the STDs or the hair removal. Perhaps an STD diagnosis prompted some respondents to start removing their pubic hair.
Another weakness was that all information was self-reported: The investigators had to rely on the survey-takers to be truthful about the number of sexual partners and their history of STDs, and to be accurate in estimating the frequency of body-hair removal. Some people might over- or under-report the number of sexual partners they’ve had, or be less likely to be forthcoming about past STD diagnoses. There is also the fact that many STDs go undiagnosed — and what if people who remove their body hair are more likely to be regularly screened for STDs, even in the absence of symptoms?
Is the case closed on the link between hair removal and STD risk? Nope. A study that follows people over time can do a better job of establishing if hair removal came before the STD — and investigators could take more risk factors into account, including condom use, HPV vaccination, and frequency of sexual contact. It could screen all participants regularly for STDs, to minimize underdiagnosis. Any ethically conducted study, however, would still have to rely on self-reported data when it comes to sexual behavior.
Remember, the best way to avoid STDs is to limit sexual contact; use dental dams and latex condoms; be vaccinated against HPV; and be regularly screened for STDs, along with your partners. Planned Parenthood health centers provide STD testing and treatment, HPV vaccination, as well as condoms and information about safer sex.
Click here to check out other installments of our monthly STD Awareness series!