Permitted to you, on the night of the fasts, is the approach to your wives. They are your garments and ye are their garments. God knoweth what ye used to do secretly among yourselves; but He turned to you and forgave you; so now associate with them, and seek what God Hath ordained for you, and eat and drink, until the white thread of dawn appear to you distinct from its black thread; then complete your fast Till the night appears; but do not associate with your wives while ye are in retreat in the mosques. Those are Limits (set by) God: Approach not nigh thereto. Thus doth God make clear His Signs to men: that they may learn self-restraint. (2:187)

They ask thee concerning women's courses. Say: They are a hurt and a pollution: So keep away from women in their courses, and do not approach them until they are clean. But when they have purified themselves, ye may approach them in any manner, time, or place ordained for you by God. For God loves those who turn to Him constantly and He loves those who keep themselves pure and clean. (2:222)

Your wives are as a tilth unto you; so approach your tilth when or how ye will; but do some good act for your souls beforehand; and fear God. And know that ye are to meet Him (in the Hereafter), and give (these) good tidings to those who believe. (2:223)