Al-Baqarah 2:222

وَيَسۡـَٔلُونَكَ عَنِ ٱلۡمَحِيضِۖ قُلۡ هُوَ أَذٗى فَٱعۡتَزِلُواْ ٱلنِّسَآءَ فِي ٱلۡمَحِيضِ وَلَا تَقۡرَبُوهُنَّ حَتَّىٰ يَطۡهُرۡنَۖ فَإِذَا تَطَهَّرۡنَ فَأۡتُوهُنَّ مِنۡ حَيۡثُ أَمَرَكُمُ ٱللَّهُۚ إِنَّ ٱللَّهَ يُحِبُّ ٱلتَّوَّـٰبِينَ وَيُحِبُّ ٱلۡمُتَطَهِّرِينَ 222

And they ask you about menstruation. Say, "It is harm, so keep away from wives during menstruation. And do not approach them until they are pure. And when they have purified themselves, then come to them from where Allah has ordained for you. Indeed, Allah loves those who are constantly repentant and loves those who purify themselves