Is ghusl and prayer obligatory when in doubt about achieving complete purity due to the continued presence of yellowish or brownish discharge and intermittent bleeding after menstruation?

If a woman sees dryness during her customary period, she may wait a day and a half. We do not know of any scholar who states that one should wait a day and a night after seeing purity, absolutely. As for the one who says that brownish discharge is menstruation but yellowish discharge is not, we do not know of any scholar who holds this view; rather, yellowish discharge can be menstruation.

Upon seeing menstrual blood, a menstruating woman refrains from prayer and what is similar to it. Upon seeing purity (dryness or white discharge), she should hasten to perform ghusl (ritual bath). If the purity is dryness within the customary period, the fatwa advises hastening to perform ghusl, and this is more cautious. If she sees blood after purity within the possible duration (15 days), she has returned to being in menstruation.

As for yellowish and brownish discharge after seeing purity: if it is within the time of her customary period, it is considered menstruation; if it is after the time of her customary period, it is not considered menstruation.

If the bleeding exceeds 15 days (including menstruation and purity), the woman is considered to be suffering from istihada (prolonged vaginal bleeding). She should perform ghusl, pray, use a protective barrier, and perform wudu' for each prayer after its time has begun. She reverts to her previous customary period if she knows it, and any excess is istihada. If she does not have a customary period, she acts according to distinguishing characteristics. If she has neither a customary period nor distinguishing characteristics, she calculates the majority of the customary period for women in her family (6 or 7 days), and anything beyond that is istihada.