When is it permissible for a woman to pray after a miscarriage and a heavy, continuous menstrual period that lasts for twenty days?

If the abortion occurs after thirteen weeks, the blood discharged thereafter is considered nifas (post-natal bleeding). If the blood reappears before forty days, it is nifas. However, if the bleeding continues after forty days, any blood beyond the forty-day mark is considered istihadah (irregular non-menstrual bleeding), unless it coincides with the woman's regular menstrual cycle, in which case it is considered menses.

If the blood exceeding forty days is istihadah, the woman must perform ghusl (ritual bath) after the forty days, take precautions, and perform wudu (ablution) for each prayer after its time has begun. She should then perform the obligatory and supererogatory prayers, and she will have the rulings applicable to women in a state of purity.