Analysis:

Effect of the Moon on Menstruation

China's Huangdi Neijing says that a woman's menstruation is once a month, "thirty days later". Li Shizhen also clearly pointed out in Compendium of Materia Medica that women should have a moon on their blood and a tide on their blood. There are gains and losses in the month, and there are tides in the morning and evening, and the monthly events coincide with them, so it is called monthly water, monthly letter and menstruation. People passing by are always waiting. " Modern medical research has proved that the normal menstrual cycle is about 28 days. This is very close to the moon's profit and loss cycle. German gynecologists have investigated the menstrual cycle of tens of thousands of women and found that when women have menstrual cramps on a full moon, the amount of bleeding may increase exponentially, while when they have menstrual cramps, the amount of bleeding is relatively small.

Tides are the function of the moon's gravity.