Having sex on your period, like any kind of sex, should be a personal choice. But when it comes to scientific research on the matter, those who are comfortable with laying down a towel may actually be getting the longer end of the stick (aka, more health benefits). "Whether it's by vibrator, penetration, manual stimulation ... it does have a medicinal effect," Dr. Maureen Whelihan, an OB-GYN, told MTV News.
Why sex on your period can actually be really awesome. Biologically, there's almost no negative health effects to having period sex when compared to sex at any other time of the month — in fact, it may offer some relief. For starters, many people say they become more aroused around the time of their periods, according to Jezebel. That may be due to the body revving itself up for reproducing, according to Medical Daily.
"My hormones are absolutely bat-shit crazy during that time of the month so my boyfriend and I both enjoy the intensity I have sexually," one woman anonymously told Cosmopolitan.
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Also, the blood is sterile and the fluids there are basically the same to those of regular sex, Whelihan said. It's made up of cervical mucus, bacteria, vaginal fluids and uterine tissue, according to Refinery29. On average, only about 40 milliliters (or about the size of a shot) of blood is released, Metro UK reported.
This means that periods also act as a natural lubricant, making sex more pleasurable and upping the chances of an orgasm, Prevention reported.
So, why the stigma against period sex? For the most part these days, "periods are either a comedic punchline or a horror show," YouTuber Kat Lazo, whose videos often address the social stigma surrounding periods, told the Independent. So where did period's notorious squirm factor come from? After all, it's believed that the ancient Greeks used period blood for medicine or fertilizer, according to the Independent. Then, at around 77 to 79 A.D., Roman historian Pliny the Elder wrote that a menstruating woman's look could kill a "swarm of bees." Later, the Bible's Old Testament declared women on their periods to be unclean, among other not-so-positive things.
From there, period blood continued to become stigmatized in society and the media as being dirty, gross and the unsexy side of a woman's body. "People are perfectly happy to see women as sex objects, but the actual biology of our bodies is apparently gross and unmentionable," Robin Holland, who made a poorly received photographed ad of a woman and a tampon string, told the Independent.
The benefits of sex on your period go beyond the pleasurable. There's a theory that orgasms can help relieve painful cramps when endorphins and feel-good hormones like prolactin are released and the muscles relax, according to Whelihan. A 2013 study of 1,000 participants found that sex can also aid in relieving headaches.
As for the notion that period cramps actually prevent women from having sex: "There's no reason why sex or penetration or hitting the uterus is going to make that worse," Dr. Tami Serene Rowen, an assistant professor at UCSF, told Men's Journal.
Having sex while on their periods can also help shorten it for some people, since the muscle spasms and uterus contractions that come with orgasms might make the body release the blood faster, Medical Daily reported.
Other research suggests that period sex can help regulate women's cycles due to exposure to the hormones from male armpit sweat, according to Women's Health.
However, period sex comes with a few caveats. It's important to keep in mind that the cervix is more open during the menstrual cycle, so there's an increased risk of transferring bacteria, which can cause STIs or other infections, according to Refinery29. It's also unadvised to have sex with a tampon in because it could get lodged too far up in the vagina.
Plus, there's still a chance that someone could get pregnant while on their period since semen can live in the body for up to five days and people can have early ovulations.
"Basically, ensuring you have good contraception and STI (sexually transmitted infection) prevention throughout the menstrual cycle should make it even more safe and enjoyable," OB-GYN Carrie Coleman told Everyday Health. As one woman told Cosmopolitan, "Life is too short to not have sex for a week every month."