Low rates of cervical cancer are about genetics—they have nothing to do with menstruation.
The authors of Flow: The Cultural Story of menstruation believe the answer is: a whole lot of them.
When menstruation attacks—according to any generic pre-teen girl—all nightmares become reality.
menstruation men·stru·a·tion (měn'strōō-ā'shən)
The process or an instance of discharging the menses.
The monthly flow of blood from the uterus beginning at puberty in girls and other female primates. Also called menses. See also menstrual cycle.