this is what I read. all healthy women are supposed to commence menstruation at time of full moon, that is also when there is high tide, water build up and other moon related changes. then after last day of full moon, 14 days(?) or so, ovulation occurs.
women used to plan fertility with moon cycles. 3 days a month are times when egg drops into the uterus and conception can occur.
as for no period, according to hotema and other naturalist authors , menses is hemorraging, loss of blood from rupture and injury from excess sex, and from toxic diet. young celibate nuns who eat clean and do not rupture thier bodies with sex are cases he sites of minimal, a few drops, or no bleeding at menses. also he cites cases of extremely sexually active women who hemorage and bleed heavily as many as 15 days of every month.
the story of the nest build up of blood is a common one. logically I would think once an egg is fertilized then it would develope in utero, not necessarily prior.
maybe men made that story up so women would not know they were hemmoraging from injury and rupture due to excess intercourse, who knows. almost everything I learned in public and private school regarding nutrition and health was special interest funded misinformation. I had to read and learn truth from "independent" sources and teachers who had no hidden ulterior profit motive or other ulterior motives, other then to teach truth. mh is so on target because he teaches us to study nature for truth.