What is the usual duration of menstruation: is it the basic eight days, or ten days despite the occurrence of dryness during the last two days?

The days of menstruation are those days during which blood is seen, regardless of its characteristics, within a period that is suitable for menstruation.

The yellowish and brownish discharges are not blood and are not considered menstruation, according to the preponderant opinion, unless they are connected to menstrual blood, or if the woman sees them during her regular menstrual days.

The regular menstrual days are the seven or eight days during which blood is seen. If these days conclude and the woman sees a yellowish or brownish discharge connected to blood, she is still considered menstruating.

If a woman sees purification by one of its two signs (dryness or white discharge), she must perform ghusl (ritual bath) and pray. Any yellowish or brownish discharge she sees after that is not considered menstruation.