How do I deal with irregular yellowish discharge (ṣufrah) that is sometimes connected to menstruation and less than 15 days, and at other times connected and exceeds 15 days? Do I consider what occurs during the usual period of menstruation as menses and perform ghusl, and then, if it exceeds that, wait 15 days, and if it does not stop, consider it istiḥāḍah?

If the yellowish discharge is connected to menstruation, the woman should not perform ghusl until she sees purity. If she sees purity before the passage of 15 days, then all of that period is considered menstruation, because the yellowish discharge connected to menstruation is considered part of it. However, if the total days of blood and the yellowish discharge connected to it exceed 15 days, then it becomes clear that the woman is a mustahadah (experiencing prolonged non-menstrual bleeding). In this case, she should do what a mustahadah does and continue to do so until she recovers.