"Such of your women as have passed the age of monthly courses, for them the prescribed period, if ye have any doubts, is three months, and for those who have no courses (it is the same): for those who carry (life within their wombs), their period is until they deliver their burdens: and for those who fear Allah, He will make their path easy." - Quran 65:4 (read more)

"Narrated by Gaber bin Abdullah: We were with the messenger of Allah, PBUH and he asked for a drink. One of his men said: "Oh Messenger of Allah, Can we offer you wine to drink?" He said Yes. He (Gaber) went out looking for the drink and came back with a cup of wine. The messenger (PBUH) asked:”Have you fermented it, even with one piece of ferment?” He (Gaber) said "yes" and he (Muhammad) drank." - Sahih Muslim 3753 (read more)

"And [as for] those of your women who (read allā'ī or allā'i in both instances) no longer expect to menstruate, if you have any doubts, about their waiting period, their prescribed [waiting] period shall be three months, and [also for] those who have not yet menstruated, because of their young age, their period shall [also] be three months - both cases apply to other than those whose spouses have died; for these [latter] their period is prescribed in the verse: they shall wait by themselves for four months and ten [days] [Q. 2:234]." - al-Jalalayn