Abu Ya'qub said: 'A woman experiencing istihadah (prolonged non-menstrual bleeding) can never be considered to be in a state of menstruation. The Prophet (peace be upon him) named her a mustahadah and clarified the days for her just as he clarified the purity from blood for the menstruating woman. This is that she should sit for the duration of her habitual menstrual days during the days of her istihadah; she does not fast and she does not pray. If her menstrual cycles vary, then the approach of precaution is more appropriate according to the people of knowledge. If she has no certainty and is ignorant of what the Prophet (peace be upon him) clarified for her regarding the days of her cycles, she would not know upon which of her times the meaning of the Prophet's (peace be upon him) statement "the days of her cycles" refers.'
Abu Ya'qub said: 'Women, during the days of their cycles, menstruate once at the beginning of the month, once in the middle, and once at the end; they shift during the months in the manner we have described. No scholar can deny what we have described regarding their shift, and they are trusted and believed regarding what they inform about themselves, as long as it is not known that they are saying what women do not menstruate in. Their status in istihadah is like their status in menstruation; if they claim regarding that what is known to occur in women, keeping in mind that what is known of women is that they do not exceed ten days.'
Abu Ya'qub said: 'Some of the people of knowledge have said: The meaning of the statement of Anas ibn Malik—even if it is not in the chain of narration because Hammad ibn Zayd and others weakened it—is that he set the dominant period for menstrual cycles at less than ten days, and he deemed her a mustahadah after ten days. Anas did not set the maximum of menstruation at one month, but he made that an optional choice based on the meaning of precaution. There is nothing in the hadith of al-Jald—despite its weakness—that states that menstruation cannot be more than ten days. The best of people in phrasing the words of the hadith is Isma'il ibn 'Ulayyah; he mentioned in the hadith of al-Jald: "She shall perform ghusl (full ablution) and fast after the ten days," and he did not say that she is not menstruating after the ten days, nor did he say she is menstruating.'
(1) Thus it is in the original, and perhaps an omission has occurred in it. (2) Thus it is in the original, and in Sharh Mughultay on Ibn Majah—where he quotes it from Harb—it reads: "ten days," which is more consistent with the context.
