{ And they ask you about menstruation; say: It is harm; therefore keep away from women during menstruation; and do not get close to them until they have become pure; and when they have purified themselves come to them where Allah has ordered you. Indeed Allah loves those who turn in repentance, and He loves those who purify themselves } Al-'baqara 222

{ Say: It is harm } ; He (may His remembrance be exalted) means by this: Say to whoever of your Companions asks you, Oh Muhammad, about menstruation, that it is harm. “Harm” is anything disagreeable by which one may be harmed; in this instance it is called “harm” due to its strong and offensive odor, its filth, and its impurity. This is comprehensive, by saying “harm”, for more than one different meaning.