“Abu ‘Abd Allah (a.s.), has said, ‘The minimum duration of Hayd (menses) free period is ten days. This is because when a woman experiences Hayd (menses) it is of a greater amount and it takes ten days. It continues and as time passes and she grows older, the duration of her Hayd (menses) reduces to three days. In this condition it does not go higher and it is not less than three days. “During her experiencing Hayd (menses) within the date of her Hayd (menses) she must stop performing Salah (prayer). If blood discharge continues for three days it counts as her period of Hayd (menses); but if blood discharge stops within a day or two, she must take Ghusl (bath) and perform her Salah (prayer). She then waits for ten days from the first day blood discharge had started. If she experiences blood discharge within that period of ten days for one or two days to complete three days, then what she had experienced before along with this one within ten days all are of her Hayd (menses). If however, for ten days after the first day she experienced blood discharge she does not experience any blood discharge, then one or two days of blood discharge is not of Hayd (menses). Such discharge can happen because of her internal problems, such as an injury or from internal problems. She must redo her Salah (prayer) missed during such one or two days in which she had stopped performing Salah (prayer). If blood discharge continues for three days, it then is Hayd (menses), which is the minimum duration of Hayd (menses). It is not necessary to perform Salah (prayer) as remedy for those missed during experiencing menses. The duration of the period free of menses is not less than ten days. If she experiences blood discharge for five days then blood discharge stops, she must take Ghusl (bath) and perform her Salah (prayer). If she experiences blood discharge after this and before ten days from theday blood discharge had stopped this as well is of her menses, and during such time she stops performing her Salah (prayer). If she experiences blood discharge which begins from the end of ten days that she had already experienced and it continues for several more days above the first ten days and the second discharge it (that which is above ten days) is of Istihadah (irregular menses) during which she follows the rules about Istihadah (irregular menses).’ He (the Imam) said, ‘Blood discharge, during her established period of menses, of yellow or red color is of menses and whatever discharge takes place after the duration of her menses is not of Hayd (menses).’”