Chapter on Menstruation
No menstrual bleeding is recognized before a girl completes 9 years of age, nor after 50 years, nor while she is pregnant.
Its minimum duration is 1 full day and night, its maximum is 15⦗1⦘ days, and it most commonly lasts 6 or 7 days. The minimum interval of purity between two menstrual periods is 13 days, and there is no maximum limit for that purity.