Sayyidah Aishah and Sayyidah Umm Salamah (may Allah be pleased with them both) both said that the Messenger of Allah (peace and blessings be upon him) would reach the morning in a state of major ritual impurity (janabah), not from a wet dream, then he would fast.
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 19892