This week I took a deep dive into the topic “period syncing”. Period syncing is the belief that your menstrual cycle will synchronise with the cycle of women who live around you. This happens because of your pheromones, which are airborne molecules that enable members of the same species to communicate non-verbally.
Really? I was curious to know what science says.
Period syncing: the McClintock-effect
The first research published on the topic period syncing was in 1971 by (female!) researcher Martha McClintock: “the McClintock-effect”. She based her research on 135 female college students living in dormitories together. She followed them for around eight cycles per woman. McClintock reported an increase in synchronisation for roommates and among closest friends, but not among random pairings in the dormitory. It was hypothesized that this was driven by the amount of time women spent together, allowing for pheromone communication.
In the meantime – almost 50 years later – we’re still trying to figure out whether period synching is real. Following McClintock’s study more research has been done but with varying results. As far as I could gauge half of all the published papers come to the conclusion that menstrual synchrony exists and the other half says it doesn’t.
Keep on tracking
Right now Clue, my favorite period app (check out our top 3 period apps as tested by Janice), is actively doing research on this topic. To date their research has shown that over time cycles are actually more likely to diverge – get out of sync – rather than sync. Read more about their study to date as well as to find out how you can participate and help us all understand whether period syncing is an urban myth or a real phenomena.
I’d love to hear your opinion on this topic as well as to hear if there are other menstruation related beliefs you’d like me to dive into. I’ll keep you posted on social media and please feel welcome to share your opinion via christel@yoni.care.
Header via Prue Stent