Quran 2:222 from Surah Al-Baqara on Divine Marvels.
وَيَسۡـَٔلُونَكَ عَنِ ٱلۡمَحِيضِۖ قُلۡ هُوَ أَذٗى فَٱعۡتَزِلُواْ ٱلنِّسَآءَ فِي ٱلۡمَحِيضِ وَلَا تَقۡرَبُوهُنَّ حَتَّىٰ يَطۡهُرۡنَۖ فَإِذَا تَطَهَّرۡنَ فَأۡتُوهُنَّ مِنۡ حَيۡثُ أَمَرَكُمُ ٱللَّهُۚ إِنَّ ٱللَّهَ يُحِبُّ ٱلتَّوَّٰبِينَ وَيُحِبُّ ٱلۡمُتَطَهِّرِينَ
English translation: And they ask you about [the] menstruation Say It (is) a hurt so keep away (from) [the] women during (their) [the] menstruation And (do) not approach them until they are cleansed Then when they are purified then come to them from where has ordered you Allah Indeed Allah loves those who turn in repentance and loves those who purify themselves
Transliteration: wayasalunaka ani al-mahidi qul huwa adhan fa-i'tazilu al-nisaa fi al-mahidi wala taqrabuhunna hatta yathur'na fa-idha tatahharna fatuhunna min haythu amarakumu al-lahu inna al-laha yuhibbu al-tawabina wayuhibbu al-mutatahirina