Pain in the abdomen causing a brown discharge can have many causes. When ovulation occurs, because the peak of estrogen stimulates the endometrium, and abdominal pain and brown discharge can occur. When this occurs, it is usually not given treatment and can heal on its own. When there is endometritis or endometrial polyps, abnormal brown discharge may also occur. Because of the brown discharge, it may cause contraction of the uterus, which may lead to pain. In such cases, it is recommended to go to the hospital for anti-inflammatory and hemostatic treatment. Also, in case of pregnancy, it may cause brown discharge. When pregnancy occurs, there is a drop in progesterone or HCG, which may also stimulate uterine bleeding, abdominal pain and brown discharge. In such a case, it is recommended to go to the hospital for treatment of birth control to avoid miscarriage.