Science Just Killed the Cherished Notion of Women's Periods Syncing


This just in: Science is taking a hacksaw to your biological friendship bracelet. The pervasive notion that women who hang out together bleed together appears to have been debunked by a recent study conducted by the University of Oxford and period and ovulation tracker app Clue. For most of us, since hitting child-bearing age, we’ve been told that our uteri recognize the ovulation patterns of other uteri belonging to women we spend a lot of time around, whether it’s your sister, bestie, roommate or co-worker, and eventually, your cycles match up. This has been a lot of fun for the follow reasons:

A.) It freaks the fuck out of men.

B.) The Craft vibes you’re putting out into the world are strong to very strong.

C.) The feeling of commiseration is really comforting; you and your favorite gal(s) simultaneously get to experience what it feels like to have a Gremlin learning the choreography to STOMP in your uterus and you also get to eat as much sodium as you want together, because you’re going to be stupid bloated anyway and those are the rules.

Like so many others, I’ve spent the last couple decades imagining my fallopian tubes air fist-bumping the fallopian tubes of my co-worker sitting across from me every month, but alas: the experts say nay. In the study of 360 pairs of women over three cycles of menstruation, 273 of them actually ended up having a larger difference of cycle timing by the end. This marks the most comprehensive study since an initial report was issued in 1971, which supported the theory of syncing as a result of “pheromone communication” and cycles aligning with that of the “alpha uterus.” The most popular evolutionary theory is that this occurs in order to minimize the risk of being repeatedly singled out by a dominant male. So the underlying message is that women’s bodies automatically protected other women’s bodies; no wonder that theory really stuck.

Clue’s data scientist Marija Vlajic gets it: “I can see how it gives you a special connection with a woman to go through that at the same time. It feeds into a feeling of connection, support, and sisterhood. Even though we do it every month, periods are personal and the thought of sharing with someone makes the idea powerful. That’s why we continue to look for patterns even when they don’t exist,” she said in an interview with The Guardian.

On the upside, this changes nothing about the fact that you and your BFF can still spend the first day of your period licking the salt off of an entire bag of pretzels. No judgement here.

-Deena Drewis