Menstruation (mammal)
Menstruation in mammals is the shedding of the uterine lining (endometrium). It occurs on a regular basis in uninseminated sexually reproductive-age females of certain mammal species.
Culture and menstruation
Across the continent of Africa, a wide variety of menstruation-related customs have been recorded.
A cloth torn from the traditional wrap (chitenge) is worn, part tied around the waist and part looped under the crutch, to catch menstrual fluid. Menarche (the first menstrual cycle at puberty) is traditionally treated as a sign that the girl is probably ready for sex and marriage, as well as for adult duties in the household. Initiation rites on menarche include instruction on sex and marital relations as well as on menstrual management. This is conducted by older women. It is taboo to talk about menstruation with men, or to learn from one's own mother. 
In some portions of South Asia, there is a menstrual taboo, with it frequently being considered impure. Restrictions on movement, behaviour and eating are frequently placed. More than one-third of girls across South Asia do not go to school during menstruation. Some of that is due to lack of safe and comfortable toilets at school (lack of water, sanitation and hygiene in schools in developing countries).
A small study in a rural area in Laos (Savannakhet) found that menstruation is considered taboo and shameful. This makes it difficult for sharing knowledge in schools and in homes. Also, there is a low level of menstrual hygiene management. This has a negative effects on the female's social opportunities in achieving a good health, move around freely and to go to school. Some menstruating women (16%) wear double-layer skirts (sinhs) while in the private sphere, compared to 54% who wear disposable pads.