It is narrated from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that a man came to the Prophet (peace and blessings be upon him) and said that he had had intercourse with his wife while she was menstruating. So the Prophet (peace and blessings be upon him) ordered him to give one dinar in charity, and if he could not find it, then half a dinar.
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 12013