In the time of Allah's Messenger (ﷺ), he divorced his wife while she was menstruating, so 'Umar asked Allah's Messenger (ﷺ) about that and he replied, "Command him to take her back and keep her till she is purified (from menses), has another period, and is then purified. If he then wishes he may keep her and if he wishes he may divorce her before having intercourse with her. That is the 'Iddah (period of waiting) which Allah commanded for the divorce of women."
وَفِي رِوَايَةٍ لِمُسْلِمٍ : { مُرْهُ فَلْيُرَاجِعْهَا, ثُمَّ لْيُطَلِّقْهَا طَاهِرًا أَوْ حَامِلًا } 1 .1 - صحيح . وهذه الرواية في مسلم برقم (1471) (5).
Narrated A narration by Muslim has:
"Command him to take her back, then divorce her when she is pure from the menstrual discharge, or pregnant."