It is narrated from Sayyiduna Abdullah bin Abbas (may Allah be pleased with him) that regarding a man who has intercourse with his menstruating wife, the Noble Prophet (peace and blessings be upon him) said: He should give charity of one dinar or half a dinar.
Hadith Referenceالفتح الربانی / كتاب الحيض والإستحاضة والنفاس / 935