Surely the number of months with Allah is twelve months in Allah's ordinance since the day when He created the heavens and the earth, of these four being sacred; that is the right reckoning; therefore be not unjust to yourselves regarding them, and fight the polytheists all together as they fight you all together; and know that Allah is with those who guard (against evil).

And (as for) those of your women who have despaired of menstruation, if you have a doubt, their prescribed time shall be three months, and of those too who have not had their courses; and (as for) the pregnant women, their prescribed time is that they lay down their burden; and whoever is careful of (his duty to) Allah He will make easy for him his affair.