It’s a simple fact of life just as natural as breathing: every 28 days or so, a post-pubescent female will shed her uterine lining if she has not become pregnant or otherwise caused her cycle to go on hiatus. Attitudes toward menstruation have varied throughout the years. In early Native and South American cultures, women retreated to “moon huts” together where they sat on mossy grass to soak up their blood and recycle it back into the earth. They meditated and made major community decisions while there. In ancient Rome however, menstruating women were considered dangerous.