She always fills pains during and after sex. what is the cause?

Many causes: There can be many causes for pain during intercourse and after. Most common is some type of irritation to the vaginal wall due to bacterial or yeast infection. Sometime the ph (acidity) of the vagina can cause pain. Some women have endometriosis which is a chronic source of pain during intercourse. Older women may suffer from lack of estrogen to the vagina, this can cause pain too.