title: Why menstruate?
authors.forename: Marilyn B
authors.initials: MB
authors.lastname: Renfree
mesh_terms: D000818:Animals; D005075:Biological Evolution; D010064:Embryo Implantation / Q000502:physiology*; D004717:Endometrium / Q000502:physiology*; D005260:Female; D006801:Humans; D008598:Menstruation; D011247:Pregnancy; D012098:Reproduction / Q000502:physiology*