Ibn Majah

"When the Messenger of Allah wanted to sleep and he was sexually impure, he would perform ablution as for prayer."

Umar bin Khattab said to the Messenger of Allah: "can anyone of us sleep if he is sexually impure?" He said: "Yes, if he performs ablution."

"A woman asked the Prophet: 'I bleed continuously and I do not become pure. Should I give up the prayer?' He said: 'No, but leave off praying for the number of days and nights that used to menstruate.'" (One of the narrators) Abu Bakr (Ibn Abu Shaibah) said in this Hadith: "Estimate the number of days in the month, then take a bath and cover your private part with a cloth and perform prayer."

"Fatimah bint Abi Hubaish came to the Prophet: 'O Messenger of Allah! I am a woman who bleeds continuously and never becomes pure. Should I give up prayer?' he said: 'No, that is just a vein and is not menstruation. Do not perform prayer during the days of your period, then take a bath, and perform ablution for each prayer, even if drops of blood fall on the mat.'"

"The Messenger of Allah was performing prayer, and I was by his side. I was menstruating, and I was wearing a wool cloak, and part of it was over him."

The Messenger of Allah performed prayer wearing a wool cloak. Part of it was over him and part was over her, and she was menstruating.

The Prophet entered upon her, and a freed slave girl of hers concealed herself. The Prophet asked: "Have her periods begun?" She said: "Yes." He tore a piece of his turban and said: "Cover your head with this."

The Prophet said: "Allah does not accept the prayer of a woman who menstruates (i.e., an adult woman) except with a head cover."

He used to become sexually impure at night, then he would want to sleep. The Messenger of Allah told him to perform ablution and then go to sleep.

"The Messenger of Allah said: 'If anyone of you has intercourse with his wife, then he wants to do it again, let him perform ablution.'"