What are the signs of purity from menstruation, what is the ruling on delaying the ritual bath (ghusl) for purification until a later time, and do yellow discharges nullify ablution?

A woman knows she has become pure from menstruation by one of two signs: al-jufūf (dryness, meaning the cotton swab comes out clean) or al-qaṣṣah al-bayḍāʾ (a white discharge that appears after menstruation). Whichever of these two signs appears first indicates purity, making ghusl (ritual bath) and prayer obligatory for her.

Any yellow or brown discharge a woman sees after achieving purity is not considered menstruation, unless it occurs during her usual menstrual period. If blood reappears after having ceased, at a time when it is possible for it to be menstruation, then it is considered menstruation, and ghusl becomes obligatory after its cessation.

Purity between two blood flows is a valid state of purity. It is obligatory to promptly perform ghusl and pray immediately upon seeing purity, before the prayer time expires. Vaginal discharges (vaginal moisture) are considered pure according to the preponderant opinion, but they invalidate wudu’ (ablution) according to the majority of scholars. A woman afflicted with incontinence of these discharges should perform wudu’ for each prayer after its time has begun.