Menstrual blood

It can be quite potent. Janet and Stewart Farrar in the Witches Bible mention something known as the Paramenses, which they describe as the increased psychic awareness of a woman about three days before the onset of a bleed. The native american women did not have to undergo the Vision Quest requested of boys because they were considered already in tune with the earth and with nature due to their monthly bleed. In times before electric light women would naturally bleed on the New Moon. Women who live or travel together will start to synchronise.