I say, and with God's success: The mustahadha is not prevented from i'tikaf, for if she is secure from contamination, she does not exit her i'tikaf. If she exits, her i'tikaf is invalidated; as narrated by Aisha (may Allah be pleased with her), she said: ‘I performed i'tikaf with the Messenger of Allah (peace be upon him) and one of his wives was a mustahadha, and she would see the redness and yellowness, so we would sometimes place a basin under her while she was praying.’ This is found in Sahih al-Bukhari 2: 716, and Sunan al-Bayhaqi al-Kabir 1: 328, and see: Bada'i al-Sana'i 2: 108, and the rulings and importance of i'tikaf, p. 57, and Allah knows best.