Why so much of this was never studied

From Learn about your cycle. General wellness information, not medical advice. Sources.

If you've felt like no one ever properly explained your own body to you, you're not imagining it. For a long stretch of modern medicine, research was done mostly on male bodies. Women were kept out of most early drug trials until a 1993 US law finally required researchers to include them, and even basic lab studies defaulted to male cells and male animals until recently.

That has had real consequences. A government review found that most of the prescription drugs pulled from the US market in the late 1990s turned out to be more dangerous for women. One common sleep medicine had its recommended dose cut in half for women decades after it launched, once researchers noticed women clear it more slowly. And study after study has found that women's pain is taken less seriously and takes longer to get diagnosed.

None of this is a conspiracy, and a lot of it is slowly improving. But it's the reason a resource like this needs to exist, and it's why we build around your own logged history rather than one-size-fits-all rules. You know your body. Our job is to help you see its patterns, not to hand you someone else's average.

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