| It may be true, but it hasn't been scientifically proven. Scientific studies have shown that there is an association between having sex during menstruation and decreased endometriosis. This does not necessarily mean that having sex caused the decrease. It may be, for example, that women who have endometriosis have less sex than other women, especially during menstruation, because they are in so much pain and discomfort. More studies need to be done to prove how having sex during menstruation and decreased endometriosis are associated.
In recent years, sex scientists have also associated a wide range of health benefits with sexual expression. Most of us are very aware of the health risks caused by having sex, but sex play is increasingly associated with many health benefits, including longevity; absence of heart disease, stroke, and breast cancer; healthy immune function; menstrual cycle regularity; relief of menstrual cramps; pain management; and improved quality of life. Future studies may tell us more about how these conditions are associated with sex play.
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