Is it obligatory to perform ghusl due to the bloody or brownish discharge that appears after a woman's normal menstrual period, given that she has an IUD inserted?

If the duration of seeing blood exceeds fifteen days, the woman experiencing the bleeding is considered in a state of istihada (prolonged non-menstrual vaginal bleeding). She must refer to her previous habit, observing the number of days she customarily menstruates, then perform ghusl (ritual bath) after that period. Any bleeding beyond her usual habit is istihada. If she does not have a previous habit, she should act according to sound discrimination (tamyiz), considering what she can distinguish as having the characteristics of menstrual blood to be menstruation, and anything beyond that to be istihada. If she has neither a habit nor the ability to distinguish, she should consider six or seven days of the month as menstruation, perform ghusl after that, and consider anything else as istihada. During the time of istihada, she must perform wudu (ablution) for every prayer, and all rulings applicable to ritually pure women apply to her.