BYAriel Scotti
Contrary to popular belief, whether they're siblings, best friends or a mother-daughter pair, women's bodies do not find a way to menstruate at the same time - ever.

Something's out of sync with this way of thinking.

According to a study done by menstrual cycle tracking app Clue, and the University of Oxford, women's periods do not magically align like the stars or Olympic swimmers because they spend a lot of time together. Contrary to popular belief, whether they're siblings, best friends or a mother-daughter pair, women's bodies do not find a way to menstruate at the same time - ever - regardless of emotional closeness, physical proximity, pillow fights or braiding each others’ hair.

"According to these results, cycles are actually more likely to diverge (get out of sync) over time," the study said.

Analyzing the data of three months' worth of cycles in 360 pairs of women showed that 273 duos, over 75 percent of them, had a larger difference in period start dates at the end of the trial than at the beginning. Only 79 pairs showed the opposite results, with the gap in their cycle start dates lessening.

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Actually, menstrual synchrony is not a thing - no matter how many manicures BFFs give each other.

(DGLimages/Getty Images/iStockphoto)

The Clue study is the latest to debunk the McClintock Effect, published in 1971, that tried to demonstrate the existence of an "alpha uterus," (not kidding) with "strong hormonal pull that influences the cycles around it to ovulate and menstruate in unison." No scientific evidence has been found to substantiate the existence of said mythical, dominant uterus.

The data was collected by Clue and lead researcher Dr. Alexandra Alvergne. "We'd like to continue to do more analysis on this topic and others in the under-researched field of female health," the study said.

Maybe having a woman at the helm will lead to more scientific-based hypothesis about the female body than an angry, bossy uterus.

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