Hadith 265
Ibn Abbas said: If one has intercourse in the beginning of the menses, (one should give) one dinar; in case one has intercourse towards the end of the menses, then half a dinar (should be given)
Hadith 2169
Narrated Abdullah ibn Abbas: If a man has sexual intercourse (with menstruating woman) during her bleeding, he should give one dinar as sadaqah, and if he does so when bleeding has stopped, he should give half a dinar as sadaqah.