The womb is a physical metaphor for consciousness itself, the void, the place of nothingness, from which all life emerges, the emptiness which is actually the fullness of all life. A place of pure potential, formless, yet the essence of all forms. Menstruation, that monthly bleeding that all women share, unites us no matter what else sets us apart. At any one time on this planet, millions of women are bleeding. http://www.mysticalfemininity.com/blog/the-power-of-conscious-menstruation