It is narrated from Sayyidah Umm Salamah (may Allah be pleased with her); she said: I was with the Messenger of Allah (peace and blessings be upon him) under the same blanket, and I felt what women feel at the time of menstruation. He (peace and blessings be upon him) said: "That is what has been decreed for the daughters of Adam." So I quietly slipped out and set my state right, then came back, and the Messenger of Allah (peace and blessings be upon him) said: "Come, get into the blanket with me." She said: So I got into the blanket with him (peace and blessings be upon him).
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 19859