
Most of the myths concerning what women can't do during their periods — hang out around bears, swim, get pregnant, share a tent with menfolk — are easily debunked. But despite all of the fun-loving, white yoga pants-wearing gals jumping around in tampon commercials, no one seems to know whether it's actually safe to practice yoga while on the rag. We talked to some experts about the possible perils of doing headstands on your period and a super fun term called "retrograde menstruation."
There are both traditional and scientific justifications for abstaining from certain yoga positions during that time of the month. The vaguest one stems from Ayurveda, an ancient Indian alternative medical system that considers menstruation a "purifying" time for women. (Because when you think "cleanse," you think blood-stained underwear, stabby cramps, and mood swings.) Yoga instructors that embrace Ayurveda principles believe that it's better for menstruating women to focus on soothing yoga poses rather than more vigorous ones, which means they'd probably be fans of my personal favorite period-time pose, The Cramp, which is when I sit on my couch holding a pillow and drinking wine. That's if they even allow them to practice at all: students of Ashtanga Yoga believe that women should refrain completely from practicing yoga for the first three days of their period. (Take this with a grain of salt, as Ashtanga traditionalists also don't practice on Saturdays, full moons, or new moons.)
Another philosophical theory concerns apana, which Dr. Timothy McCall, the medical editor of Yoga Journal, describes as "the hypothesized downward … force that is said to help facilitate things such as bowel function, urination, and menstrual flow." Many believe that reversing apana interferes with the period in a negative way. There's a medical explanation that goes in tandem with this: some think that inverting your body can prompt "retrograde menstruation," which is basically when your period flows backwards, up into your fallopian tubes. (Lovely, right?)
Retrograde menstruation can lead to endometriosis, which causes painful lesions, irregular bleeding and infertility issues. (Gross! The white yoga pants-wearing ladies would not approve.) So that's another reason why some instructors warn women to stay away from inversions (positions in which you raise your feet over your head) during the heaviest part of their flow. "There are wonderful poses for women on their periods," said Christine Stein, an Iyengar yoga instructor who leads workshops on women's health and seems to think we are all delicate ladyflowers. "The practice should just change a little so that women can keep the uterus area soft during their periods. There's a lot going on down there."
But many doctors, including McCall, say this idea is outdated: a study found that retrograde menstruation naturally occurs in 90 percent of women, most of whom never develop endometriosis, so it's unlikely that a brief headstand could be all that dangerous. However, Mary Pullig Schatz, M.D, who helped debunk the endometriosis theory, still advises against inverting while menstruating, due to potential "vascular congestion," aka a heavier period. And no one wants that — although you'd probably have to stay inverted for a good amount of time to really affect your flow, according to longtime yoga teacher Barbara Benagh, who pointed out a number of other inversion theory inconsistencies in a Yoga Journal article. For example, in his book, Yoga: The Path to Holistic Health, the founder of Iyengar yoga — a discipline that strongly believes women shouldn't do inversions while menstruating — actually recommends practicing inversions to alleviate menstrual problems such as heavy flow and irregular periods.
Benagh also noted that instructors who recommend avoiding inversions often say nothing about other poses that invert the uterus in the same way. "Practicing while menstruating is a confused topic to say the least," she told me in an email. "The taboo is steeped in a ‘tradition' that has no antiquity and is influenced by Indian culture."
It seems like anti-inversion theories simply make sense to many, including both ancient Indian Yogis and modern day instructors: the idea of blood flowing upwards freaks people out. But women — at least those of us who can only hold a headstand for a few seconds — should feel safe making their own decisions about when to practice yoga. "To me the bigger question is whether you are listening to your body," McCall told us. "If you are tired and crampy, then not only shouldn't you be doing strong inversions like headstands in the early days of your period, but you probably should also be refraining from multiple sun salutations, arm balances and other strong poses, in favor of a gentler practice. I believe, however, that if it's later on in your period, your flow is light, and you otherwise feel good, that going upside down for a minute or two is unlikely to cause problems."
Benagh also put it well in her email: "My opinion [is that] every woman needs to decide for herself since we all have such different experiences of the cycle. Personally, at the ripe age of 62, I'm glad my cycle is no more!"
Image by Jim Cooke, source image via ivaskes/Shutterstock