Chapter: Menstruation

Menstruation (hayd) is blood discharged by the womb when a woman reaches maturity, and then it becomes habitual for her at known times, for the wisdom of nurturing a child. When she becomes pregnant, this blood is diverted, by the permission of Allah, to nourishing the fetus; this is why a pregnant woman does not menstruate. When she gives birth, Allah the Exalted, through His wisdom, transforms it into milk with which the child is nourished; this is why a nursing woman rarely menstruates. When a woman is free of pregnancy and nursing, this blood remains with no outlet, so it settles in a place, then it generally exits every month for six or seven days. It may exceed that or be less, and the woman's month may lengthen or shorten, according to what Allah the Exalted has implanted in human nature. It was called menstruation (hayd) from their saying: 'The torrent flowed' (hada al-sayl). Umara ibn Aqil said:

The dust-raisers stirred up their pebbles, and the torrents of the gushing floods menstruated over them.

The Sacred Law has attached rulings to menstruation. Among them is that it is forbidden to have intercourse with a menstruating woman in the vagina, due to the saying of Allah the Exalted: {And they ask you about menstruation. Say, "It is harm, so keep away from women during menstruation. And do not approach them until they are pure. And when they have purified themselves, then come to them from where Allah has ordained for you.}

Among them is that it prevents the performance of prayer and fasting, based on the evidence of the saying of the Prophet (may Allah bless him and grant him peace): 'Is it not the case that if one of you menstruates, she neither fasts nor prays?' Narrated by al-Bukhari.