There are certain things we know about our periods like how it makes us poo more and gives us the urge to eat everything in sight thanks to a spike in cortisol.
Then there are other quirks that science isn’t quite sure about, like whether periods actually sync with one another either.
The moon and females and fertility have long been seen as linked. People have thought that, just like the ebbing and flowing of tides, menstrual cycles are linked to the moon with many claiming that you ovulate around the full moon and have your period near the new moon.
Some even claim that these patterns can be split into two types of menstruation: 'white moon' and 'red moon'menstruation and that there are more births when there is a full moon.
Even the actual words ‘menstruation’ and ‘menses’ come from the Latin word ‘mensis’ which means ‘month’ and relates to the Greek word ‘mene’ which means ‘moon’.
Apparently though, the idea that periods sync to the lunar cycle is not true.
Period tracking app Clue analysed 7.5 million cycles and found no correlation between lunar phases and the menstrual cycle of start of the period. Dr Marija Vlajic Wheeler, one of their data scientists looked at the data of their users that saw that ‘period start dates fall randomly throughout the month, regardless of the lunar phase.’
The link it seems, come from the very similar length of the lunar and mentstrual cycles: the average length of a menstrual cycle is 29 days and the lunar cycle is 29.5. This, say Clue, means that statistically one in two women will have their period start either three days before or after the full or new moon, giving the impression that cycles are linked to the lunar cycle and, for some, they will be.
As Clue say, people may find that ‘observing the lunar cycle in relation to their menstruation has meaning for them personally.’ And although it may not be entirely backed up by the science, it's not a bad way to decipher when your period will be turning up that month.
Like this? You might also be interested in:
Every Question You've Ever Had About Your Periods, Answered.
Follow Chemmie on Twitter @chemsquier
This article originally appeared on The Debrief.