The Prophet ﷺ said, "If a man has intercourse with his wife while she is menstruating, let him give half a Dinar in charity."
حدثنا محمد بن الصباح البزاز حدثنا شريك عن خصيف عن مقسم
عن النبي ﷺ قال إذا وقع الرجل بأهله وهي حائض فليتصدق بنصف دينار
[Its chain is daif] Tirmidhi narrated it, in the book of Purification, chapter on what has been said about the expiation for that, hadith no. 136, from the hadith of Sharik al-Qadi, with this chain, and its chain is daif, but the preceding hadith suffices in its place.