1. Women who spend more time together end up having periods at the same time. Myth or fact?
Have you ever felt that your roommate or your colleague’s periods date has synced with yours even though your cycles were far apart? Agree or not, we all have experienced this at some point in our lives. But is it just by chance or is there any logic behind the same? To clear the confusion, read ahead.
2. What is period syncing?
It is a popular belief that women who spend too much time together start menstruating on the same dates every month. Periods syncing is also called menstrual synchrony, McClintock effect.
It is believed to be a theory that when women come in contact with other women who are menstruating, the pheromones influence each other so that eventually your menstrual cycles line up together. Women believe that periods syncing is real. But medical literature does not have a solid case to prove that it happens.
3. What McClintock effect?
The idea of periods syncing has been passed by grandmothers to mothers and from mother to their daughters for centuries. But the medical community started taking the idea seriously when a researcher named Martha McClintock conducted research on 135 college women, who were made to live together to see if their menstrual cycles got synced.
The study did not test other factors but only tracked when women’s monthly bleeding began. It was found that women’s periods actually got synced up. Post this, periods syncing was referred to as the ‘McClintock effect’.
4. The recent research
With the invention of multiple period tracking apps, which store the digital records of women’s menstrual cycle, there is a lot of data available to study and understand if period syncing is for real.
In 2006, a new study and review of the literature asserted that women do not sync up their periods. This study collected data from 186 women living in groups in a dorm in China. The only period syncing that occurred was within the realm of mathematical coincidence.
5. Another study
A study conducted by Oxford University and a period tracking app company had the biggest discovery. The study collected data from 1,500 people and found that it’s unlikely that women can disrupt each other periods cycles just by being in close proximity to each other.
Another study conducted in 2017 found that 44 per cent participants of their study experienced period synchrony. Even period symptoms like menstrual migraine were also more common in living together. This indicates that women might influence each other’s periods in ways beyond the dates of their menstruation.
6. Synchronisation with the moon
The word ‘menstruation’ is a combination of Latin and Greek words meaning ‘moon’ and ‘month’. People believe that women’s fertility rhythms were related to the lunar cycles. And even some research suggests that your period is synced with moon’s phases.
According to an older study conducted in 1986, 1 in every 4 women has their periods during the new moon phase.
7. Verdict
It is hard to tell if periods syncing is real as we do not know for sure if the pheromones (chemical signals that we send to the other humans around us) on which the study hinges can actually influence your periods.
Periods sync might happen more due to the laws of probability rather than anything else. For example, if you have your periods for one week of the month and you live with four other women, the odds are at least two of your will have your periods at the same time.