Sunan an-Nasa'i, 209

Rapporté par 'Aïcha : Umm Habibah bint Jahsh, mariée à 'Abdur-Rahman bin 'Awf, avait des saignements hors règles (Istihadah) et ne devenait pas pure. On a parlé de sa situation au Messager d’Allah (ﷺ) et il a dit : « Ce n’est pas les règles, c’est un coup dans l’utérus, alors qu’elle calcule la durée de ses règles habituelles, qu’elle arrête de prier pendant ce temps, puis après cela, qu’elle fasse le Ghusl pour chaque prière. »

It was narrated from 'Aishah that Umm Habibah bint Jahsh who was married to 'Abdur-Rahman bin 'Awf suffered from Istihadah (non-mentrual vaginal bleeding) and did not become pure. Her situation was mentioned to the Messenger of Allah (ﷺ) and he said:'That is not menstruation, rather it is a kick [1] in the womb, so let her work out the length of the menses that she used to have, and stop praying (for that period of tie), then after that period of time), then after that let her perform Ghusl for every prayer.'" [1] A kick in the womb: in other narrations means "A kick from Shaitan,", meaning that the Shaitan uses it to confuse her about her religious commitment