After an unsuccessful IVF procedure, does a woman consider the blood she sees, which is more than her usual period, as istihada (irregular bleeding outside of menstruation)?

If the menstrual bleeding continues for longer than its usual duration, but does not exceed 15 days, then the excess is considered part of the menses. However, if the bleeding exceeds 15 days, the woman is considered to be experiencing istihadah (definition) (non-menstrual vaginal bleeding), and she should not abandon prayer or fasting. She can distinguish between menstruation and istihadah by color or odor. If she cannot distinguish, then her menses is only for the duration of her usual habit.

Some scholars are of the view that the usual habit is what is considered in determining the duration of menstruation for a woman whose bleeding exceeds 15 days. So, she observes her usual days of menstruation, and anything beyond that is istihadah. Istihadah is the flowing of blood outside of its usual times due to illness or a vein, and nothing that is forbidden to a menstruating woman is forbidden to a woman experiencing istihadah. However, she must perform ablution for each prayer after the time for that prayer has begun.