Is the yellowish or brownish discharge before the onset of menstrual bleeding considered menstruation, thereby necessitating the omission of prayer and fasting?

Yellowish and brownish discharges during the time of menstruation are considered menstruation. If they occur after purification, they are not considered anything. So, if the yellowish discharge appears immediately before menstruation, and blood then follows it continuously, and it is accompanied by the known menstrual pains, then it is menstruation, and abstaining from what a menstruating woman abstains from is obligatory until purification. However, if the situation is not as described, then it is not considered anything. Hormones that affect the menstrual cycle should not be taken except for the treatment of an illness.