Despite the fact that most women get their period every month or so, it's still a surprisingly mysterious phenomenon. Many of us know approximately when it's coming and what to do when it arrives, but as far as the mechanics of how our bodies actually function, there's still plenty to learn. Shed some light on the subject by reading these eight surprising facts about your menstrual cycle.
Ovulation, which lasts one to two days, refers to the phase in your menstrual cycle when your ovary releases an egg for fertilization. According to Dr. Wider, subtle changes that may happen before and during ovulation are breast tenderness, a rise in basal body temperature and an increase in cervical mucus—which are all biology's way of prepping for fertilization. While some may not notice any specific changes, others feel ovulation more pointedly. "Some women experience mittelschmerz, which is lower abdominal pain that occurs with ovulation," she explains. Just before ovulation, with the help of estrogen, a follicle develops within the tissue of the ovary. When the egg is released, the follicle ruptures, causing fluid to be released into the abdominal cavity, which can be irritating for some women. "Some even feel it on one side of their abdomen one month and on the other the next month, since our ovaries take turns releasing eggs."
"An average cycle is typically 28 days, though it's normal for it to be anywhere between 21 and 35 days," says Jennifer Wider, MD, spokeswoman for the Society of Women's Health Research and author of The Savvy Woman Patient. When calculating the length of your cycle, day one is the first day of your period, and the last day is the day before your next period arrives. According to Dr. Elizabeth Lyster of Holtorf Medical Group in California, it's the first phase of the menstrual cycle that varies the most from woman to woman. "The time from day one of your cycle to ovulation can be anywhere from one to three weeks," she says, "while the second phase, which occurs post-ovulation, lasts about 14 days for everyone." It's also normal for your cycle's length to vary from month to month—stress, diet and a plethora of other factors play a part. A common remedy for irregular or heavy periods that don't have a more serious underlying cause is birth control pills, which can help regulate your cycle.
Women who experience lower back and upper leg pain during their period can attribute those symptoms to a network of nerves within the pelvic region. "It's like a nest where the twigs are all intertwined," says Dr. Lyster. "So if something feels irritating on one side [like the abdomen], you may feel it on the other side [such as the lower back] just as easily." Menstrual cramps also feel different than cramps that occur elsewhere on your body. Most women will tell you that instead of a sharp, singular pain, menstrual cramps feel more like a dull soreness. "That's because, like the bladder and arteries, the uterus is a smooth muscle," says Christine Y. Ko, MD, a general practitioner in San Diego. "Unlike with the striated, skeletal muscles in your leg, when your uterus contracts you'll feel more of an undefined, deep ache."
If you've ever heard that sex is a good remedy for cramps, you might want to take that advice with a grain of salt. "For many women it's pretty much a myth," says Dr. Ko. Orgasms cause smooth muscle contractions of the vagina and uterus that are pleasurable for many, but can be uncomfortable for some. Plus, when the cervix is touched, which sometimes happens during sex, it can cause uterine cramping. Furthermore, according to Whitney Pollock, DO, an ob-gyn specialist in Pottsville, Pennsylvania, semen contains prostaglandins, which help simulate labor by causing uterine contractions—yet another way sex can cause cramping.
A study from the journal Psychological Science found that when men smelled T-shirts worn by women who were ovulating, their testosterone levels raised significantly more than when they sniffed shirts worn by non-ovulating women. These findings imply that men exhibit a biological urge to mate with women who are ovulating. Studies like this one suggest that "there are fundamental ways that women attract men at their most fertile time," says Dr. Wider. Many women report a raised libido during ovulation as well, and research has shown that they may act more flirtatious during this time.
Birth control pills administer a dose of artificial hormones that mimic the ones your body naturally makes. One of the ways these hormones prevent pregnancy is by suppressing ovulation, which can temporarily throw your body's natural rhythm out of whack. Once you've stopped taking the Pill, your cycle will return to its natural rhythm—but that can take some time. For example, though it's possible to get pregnant right after you stop using this form of birth control, most doctors will advise waiting until your period returns to normal, which signals that you're ovulating regularly again. The same is true when it comes to diagnosing menstrual-related conditions. "Usually doctors will wait up to six months after a patient has stopped taking the Pill before they start looking for something that's causing abnormal periods," says Dr. Wider.
Advil and chocolate aren't the only solutions when it comes to relieving headaches, abdominal pain and bad moods—certain vitamins and minerals can help ease PMS symptoms, too, so ask your doctor for the green light to try them. Studies have suggested that calcium can quell smooth muscle cramps and vitamin D can improve mood. Magnesium can also help alleviate irritability as well as muscle aches. And, according to Dr. Wider, the whole B vitamin complex—which includes B12, B6 and folic acid—helps ease period symptoms like cramping and cravings. Finally, many herbal teas on the market boast PMS-reducing effects. While they don't usually contain the vitamins above, many women do report reduced symptoms after taking them. Whether it's the placebo effect or not, Dr. Wider is comfortable recommending them as a safe method for relieving menstrual pain.
If you frequently suffer from yeast infections, you may have noticed that they rarely begin during your period. According to Dr. Wider, that's because menstrual blood can raise the pH of your vagina, making it difficult for yeast to thrive, and therefore lowering your chances of infection. However, that elevated pH, along with hormonal fluctuations, can also cause some women to develop more bacterial infections during their period than usual, which can be identified by extra discharge and a fishy smell. If you have these symptoms, see your doctor for treatment.