What is the ruling on the prayer of a wife who has had an IUD inserted to prevent pregnancy due to health conditions, and whose menstrual cycle has become irregular, so she does not know when it begins or ends, and how does she determine her state of purity for prayer?

If the total number of bleeding days and the intervening days of purity exceeds fifteen days, and the period of continuous purity does not reach thirteen days, then the woman is considered to have Istihada (non-menstrual vaginal bleeding). However, if the duration of the bleeding days and the intervening purity does not exceed fifteen days, then all of it is considered menstruation, and the purity occurring within the menstrual period is considered a valid state of purity.