What is the Sharia ruling regarding a husband who has intercourse with his menstruating wife after being informed of her menstruation, and does the wife bear any sin for that?

A wife is not permitted to obey her husband's request for intercourse during menstruation, based on the Almighty's saying: "So keep away from women during menstruation." The husband does not bear her sin unless he forced her. She must seek forgiveness and repent, and instruct her husband to repent as well. It is recommended for the husband to offer expiation: a gold dinar if intercourse occurred at the beginning and peak of menstruation, and half a dinar if it was towards the end and weakening. Some scholars hold that expiation is obligatory for both the husband and the wife if she complied.