Do not count her menstrual days as part of the i'tikaf, and she must leave the mosque as a duty; due to his saying, peace be upon him: "I do not permit the mosque for a menstruating woman or a person in a state of major impurity." She should make up her menstrual days and connect them with the month so that the continuity is not broken. If she does not connect them, she must repeat them; because this amount of continuity is within her capacity, and what is excused from her is known to be beyond her capacity. However, if she vowed to perform i'tikaf for ten days and menstruated during that time, she must resume it. Refer to: Al-Mabsut 3: 121.