Can husband and wife sex each other in Islam?

No intercourse during the wife's period. Because at that moment dirty blood is flowing out of the vagina which might cause health issues and infection

No anal sex because the anus is not made to be a part of sexual intercourse experience. Designed to bring "things" outward, not inward.

If the wife is pregnant and is nurturing milk inside the breast, the husband is not encouraged to suck the milk as it is created for the baby.

Some say that swallowing the semen is also not allowed