the Prophet said about a man who had sexual intercourse with his wife while she is menstruating: "He should give half a Dinar in charity." (Using translation from Tirmidhī 136)
قَالَ النَّبِيُّ ﷺ فِي الَّذِي يَقَعُ عَلَى امْرَأَتِهِ وَهِيَ حَائِضٌ «يَتَصَدَّقُ بِنِصْفِ دِينَارٍ»