Musannaf Ibn Abi Shaybah

Hazrat Hammad (may Allah have mercy on him) says that if a person divorces his wife while she is in a state of istihada (non-menstrual bleeding), and if her third menstruation comes before the usual period of menstruation, then her husband does not have the right to take her back. She should neither perform ghusl (ritual bath) nor pray until more days have passed than the number of days she usually menstruates.