What is the ruling on prayer, fasting, and intercourse when a spot of blood appears at the beginning of an irregular menstrual cycle, and when does the legally recognized menstrual period begin: from the first drop of light blood or from the onset of actual menstruation?

Scholars have differed regarding the minimum duration of menstruation. The majority are of the opinion that it is one day and one night, while the Malikis and Sheikh al-Islam Ibn Taymiyyah held that there is no minimum limit for it, which is the more cautious view.

Thus, if a woman sees blood at a time when it could be menstruation, she is considered menstruating. If she sees purity (cessation of bleeding), she must perform ghusl, and this purity is considered valid.

If there is no minimum limit for menstruation, then if a woman sees blood, she is menstruating. And if she sees purity (dryness), she must perform ghusl, pray, and fast. If the blood returns, she reverts to being in a state of menstruation, unless the total duration of the two bleeds and the intervening period of purity exceeds fifteen days (the maximum duration of menstruation).

According to the view of the majority, a woman is not considered menstruating until the total amount of blood she sees reaches one day and one night.