If you're a woman with a period, the thought that menstruation exists only to curse your life has probably crossed your mind. But despite the aches and annoyances that come with a period, its purpose is not to mess with your day -- or your favorite pair of white jeans. In fact, we have "Aunt Flo" to thank for the continuation of humanity.
Only a few species on the planet have a menstrual cycle, and female humans are among this lucky bunch. The TED-Ed video above illustrates why the ladies of this planet experience a cycle.
Every month that pregnancy doesn't happen, the period removes anything in the womb, including unhealthy embryos and unfertilized eggs, that could pose risk to a woman's health. This protects the woman from infection and keeps only healthy embryos around, increasing the likelihood of a safe pregnancy and birth, if and when the time comes.
To learn more about this miraculous biological process, watching the video. It won't make your cramps go away, but it might help you recognize the mighty awesome powers of being a woman.
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