The istibra' of a woman who has menstrual cycles is with two menstrual cycles, and we do not know of anyone who holds this view. Sa'id ibn al-Musayyib, 'Ata', al-Dahhak, and al-Hakam said regarding a slave woman who does not menstruate: 'She is verified by one month and a half.' Hanbal narrated this from Ahmad, for he said: 'Ata' said: If she does not menstruate, then it is forty-five nights.' My uncle said: 'I hold the same view; because the waiting period ('iddah) of a divorced slave woman who has reached menopause is likewise.' The famous view from Ahmad is the first one. Ahmad ibn al-Qasim said: 'I said to Abu 'Abd Allah: How did you place three months in the place of one menstrual cycle, when God in the Qur'an only placed one month in the place of every menstrual cycle?' He replied: 'We only stated three months because of pregnancy, for it does not become apparent in less than that. Indeed, 'Umar ibn 'Abd al-'Aziz asked about that and gathered the scholars and the midwives, and they informed him that pregnancy does not become apparent in less than three months, and this pleased him.' Then he said: 'Do you not hear the statement of Ibn Mas'ud: "The nutfah (drop) is forty days, then an 'alaqah (clot) for forty days, then a mudghah (chewed-like lump) after that."' Abu 'Abd Allah said: 'So when the eighty [days] have passed, it becomes after that a mudghah, which is flesh, so it becomes apparent then.' And he said to me: 'This is well-known among women.' As for one month, there is no meaning in it, and we do not know of anyone who holds this view. The basis for her istibra' with one month is that God Almighty placed the month in the place of the menstrual cycle, and therefore the months differ according to the difference in the menstrual cycles. Thus, the waiting period of a free woman who has reached menopause is three months, in place of three menstrual cycles, and the waiting period of a slave woman is two months, in place of two menstrual cycles. For a slave woman undergoing istibra' whose menstruation has ceased, [it is] ten months: nine for pregnancy and one month in place of the menstrual cycle. Therefore, it is necessary that it be a month in place of the menstrual cycle here, just as in the case of one whose menstruation has ceased. If it is said: 'But there, something was found that indicates the absence of pregnancy, which is the waiting period of nine months,' we say: 'And here, there is something that indicates the absence of pregnancy, which is menopause; so they are equal.'