Sure, by now you’ve probably already heard that when women spend extended periods of time together, their cycles can sync up. If you live with another woman, or perhaps just work next to her every single day, you both will most likely experience something called “Menstrual synchrony,” which is the idea that women who live together get their periods around the same time each month.
It was once just a bit of a rumor, but recent research suggests a few different reasons why this seems to happen.
Back in 1971, a psychologist named Martha McClintock had conducted a study that suggested ladies who live close together eventually wind up with Aunt Flo coming to town around the same time each month. Her research, however, was not strong enough to be proven fact. But, even though it’s not proven yet, researchers suggest there may actually be a few different reasons why this seems to happen.
Our pheromones — those unique, odorless chemicals our bodies release — may be the culprit. It’s also possible that women who are consistently in close proximity to each other may also have similar diets, routines, and stressors — which are all factors influencing our cycles each month.
Also, if you and your roommate or coworker are both on the Pill and start on the same day (Sunday), then that could also be a cause. This actually makes the most sense and would be the easiest to figure out.
Regardless of whether or not it’s true, miserly loves company. It’s so much better when your BFF is also craving chocolate ice cream and dying to just sit on the couch with you and watch reruns of Sex and the City. Whether you believe these theories or not, enjoy the fact that you have a partner in crime every month, who will absolutely share your oh-so-fun PMS feels.