Sometimes, people with a pituitary gland tumor do not have any of these changes. Or, the cause of a symptom may be another medical condition that is not a pituitary gland tumor, symptoms include:-->Headaches->Vision problems->Changes in menstrual cycles in women->Impotence, which is the inability to achieve or maintain an erection in men and is caused by hormone changes->Infertility, meaning the inability to have children->Inappropriate production of breast milk->Cushing Syndrome, a combination of weight gain, high blood pressure, diabetes, and easy bruising that is caused by overproduction of ACTH->Acromegaly, the enlargement of the extremities or limbs and thickening of the skull and jaw caused by too much growth hormone->Unexplained tiredness->Mood changes->Irritability