Periodic discharge, mainly of blood, from the womb, beginning between the age of 13 to 15 and lasting from 2 to 8 days. It recurs approximately every 28 days, ceasing during pregnancy and lactation, and continues until the age of 44 to 50 years. It causes considerable inconvenience, whether physical or through increase in tension. It may be associated with menstrual pains and headaches. It may provoke various forms of discrimination against the woman at that time, or be used to justify such discrimination at any time.
As an indication, the market for female sanitary protection (including female hygiene tampons and sanitary towels) in the UK in 1986 was £123 million.