5 Unexpected Things That Happen During Period Sex

Pregnancy scares are an unfortunately all too common occurrence when you're a sexually active heterosexual/bisexual woman, or if you associate with sexually active heterosexual/bisexual women. One night last month, my phone began wildly vibrating with a string of texts from a panicked friend who was debating whether or not she could be pregnant after having sex while she was on her period. She had been experiencing a heavy flow throughout that whole week, including right up until the moment she had sex. Immediately following sex, her period was extremely light, and her cycle ended up being two days shorter than normal. The morning after she frantically texted me, she called her gynecologist's office to gain some insight into what might be happening in her uterus. That's when she found out that lighter, shorter periods frequently happen when engaging in sex while menstruating. And lo and behold, she wasn't pregnant and her next period showed up right on time. We were all surprised by this convenient fact about our bodies, and wondered what other unexpected things happen when you have period sex?

I spoke to Dr. Alyssa Dweck, OB/GYN, Assistant Clinical Professor at Mount Sinai School of Medicine, and author of V is for Vagina: Your A-Z Guide to Piercings, Periods, Pleasure, and So Much More, about the ways our bodies react to period sex. Dr. Dweck tells Bustle about the incredibly positive effects experienced by some women, as well as the important precautions we should take to protect our health when we are in this vulnerable state.

Dr. Dweck also shared some issues she has seen from multiple patients over the years; keep these things in mind if you and your partner decide to surf the crimson wave together. 1) Don't have sex with a tampon still in your vagina. 2) If you and your partner decide to have shower sex in hopes of avoiding stained sheets and you're using lube, remember that it is very easy to fall all over the place in such a slippery environment. So be careful.

To the ladies who aren't worried about messy sheets or the shame that this patriarchal society tries to attach to a menstruating body, here are some things you can expect to happen when you have period sex:

1. Your Period Can Get Lighter

So why did my friend (and why do a lot of women) experience a lighter or shorter period after having penetrative sex during menstruation? Dr. Dweck explains that while the medical reasoning isn't exactly known, it most likely has to do with orgasms helping the body to expel prostaglandins, or cells in the uterus lining that contribute to menstruation and cramps. Basically, sex to orgasm can help your body get rid of all that stuff faster. "During orgasm, the uterus contracts, and therefore blood may just get pushed out faster and the flow may seem a little bit different," Dr. Dweck tells Bustle. "And [orgasm contractions pushing out] prostaglandins may have a role; they are secreted chemical compounds responsible for menstrual cramps."

Dr. Dweck also adds that other factors could possibly be at play besides orgasm, such as side effects from the kinds of medications many women take during that time of the month. "A lot of women will take medication that counteracts prostagladins, like advil or motrin," which are also blood thinners, "so it's possible that a lighter flow may have something to do with medication."

2. Your Cramps Might Go Away

Your flow may not be the only alleviated aspect of your period. It is very common for menstrual cramps to be lessened as well. Dr. Dweck explains, "I'm not sure of the exact scientific mechanism, but it may have something to do with the release of prostaglandins and the release of endorphins from orgasm." Endorphins are feel-good chemicals released by your brain, often during physical activities. "Your sensation of pain is lessened as a result of the endorphins," Dr. Dweck continues. "I think there is also something to be said for uterus contractions that occur during orgasm. If there are clots or blood in the uterus, they will get pushed out faster" along with the prostaglandins.

3. It's Easier To Contract STIs

So far, we've discussed some of the greatest potential benefits of period sex, but it's important to acknowledge the less positive aspects so that we can protect ourselves. It is much easier to contract or spread an STI while you are menstruating, for reasons ranging from the presence of blood to otherwise harmless abrasions sometimes caused by tampons. Dr. Dweck told me, "Blood in general is a medium for bacteria. If blood in the vagina or uterus is exposed to some bacteria during unprotected sex, there are more places for bacteria to grow." It is also very important to consider how your partner will be affected.

Dr. Dweck continues, "Blood in and of itself can carry STDs, so you could give your partner something if you are positive and having unprotected sex," such as blood-borne STIs like HIV, syphilis, and hepatitis. "Women who are using tampons during their period may create little microabrasions in their vagina. So when they pull out the tampon to have sex, if that makes little cuts, then they would become more susceptible to contracting something," she says. The cervix is also open wider during menses, making it easier to be exposed to an STI. So remember to wear a condom!

4. For Some Women, Sex Can Be More Pleasurable

Now back to the awesome stuff that happens. While this is certainly not the case for every woman, some women experience more intense pleasure when they have sex on their periods. Dr. Dweck shared multiple reasons for these sensations. For one, it is common to "have a much heightened libido" while menstruating, especially during the first days of your cycle. A heightened libido means an increased sex drive. It is also common to have more lubrication, thanks to all of the blood and mucous that your body is producing down there. These factors combined lead to excellent sexual experiences for women and partners who want to engage in period sex.

However, some people's libidos shrink during this time. "Some women are so freaked out about the mess it will make, or are embarrassed to be seen in that state by a partner, so her libido can be dampened for that reason." There are also many women who are simply in too much physical pain to even care that orgasms might help their cramps.

5. You Can Potentially Still Get Pregnant, Though It's Less Likely

Lots of people assume that it is impossible to get pregnant if they have unprotected sex on their periods. As Dr. Dweck explains, it is not very likely that you will get pregnant — but that is definitely not the case for all women. It depends on the regularity of your cycle, so it is always wiser to use some form of birth control. However, Dr. Dweck explained the science that decreases some women's chances of conceiving during menses; specifically, women need to have the truest scientific definition of a period. "If you're really having your period, then you ovulated two weeks ago, you did not get pregnant, and your shedding uterine lining. If that is really the case, then you can't get pregnant because the window of fertility is gone."

The thing is that when you have an irregular cycle, as many people do, then you don't have that kind of period timed exactly two weeks after ovulation. It's more scientifically accurate, Dr. Dweck says, to describe this as "vaginal bleeding."

Most importantly, this means that you could be fertile during your period. Dr. Dweck explained that this is especially the case for women who suffer from Polycystic Ovary Syndrome (PCOS), as their cycles are extremely irregular, making their fertile windows almost impossible to predict.

So go right ahead and have tons of period sex for the heightened arousal, lighter flow, and alleviated cramps, but use protection!

Want more women's health coverage? Check out Bustle's new podcast, Honestly Though, which tackles all the questions you're afraid to ask.

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