Is the bleeding a woman experiences after uterine surgery considered menstrual blood?

The blood flowing from a woman's vagina after surgery, if menstruation is impossible—such as after a hysterectomy—is neither menstrual blood nor abnormal vaginal bleeding (istihada). Her ruling is the same as that of a woman who sees yellowish or brownish discharge: she prays, fasts, performs ablution (wudu), and ties a cloth over her private parts for each prayer after its time has begun. However, if it is possible for her to menstruate, then her ruling is that of a woman with abnormal vaginal bleeding (mustahadah), as indicated by the Prophet's (peace be upon him) saying to Fatimah bint Abi Hubaysh: "That is but a vein, and it is not menstruation. So, when menstruation comes, stop praying."