Answered by SecondMedic Expert
Gynecologist · Gynecology, Women and Reproductive Health
The phenomenon of menstrual synchronization, also known as the ‘McClintock effect’ after its discoverer Martha McClintock, is a widely researched topic in psychology. Studies have shown that female roommates or close friends with regular menstrual cycles tend to synch up over time - on average about 8-10 weeks.
Various theories have been put forward to explain this phenomenon including theory of odour exchange and emotional synchrony between women living together. The most widely accepted explanation however is pheromone theory; which suggests that when women live together they exposed to each other’s pheromones which influence the production of reproductive hormones like oestrogen and progesterone in their bodies causing their periods to become more synchronized.
Regardless of what causes this synchronization the results are undeniable; Women who live together end up experiencing similar health benefits associated with having a regular cycle such as improved sleep, better immunity and improved skin health due to hormonal balance.
