ما الحكمة في عدم طلاق المرأة وهي حائض؟

The Islamic law prohibited divorce during menstruation to prevent harm to the woman by prolonging her waiting period (iddah). This is because the menstrual period during which she is divorced does not count towards her iddah, without any disagreement among scholars. This is due to Allah's command for a complete three menstrual cycles (quru'), and for the cycle in which she was divorced, there isn't enough left of it to complete the three.