Constipation is often thought of as a decrease in frequency of stools and many people believe they are constipated if they do not have a bowel movement each day. This is not correct, as many persons have as few as three bowel movements each week and are healthy. For many people, constipation means too much straining with bowel movements, passage of small hard stools or a sense that they have not completely emptied their bowels. The American College of Gastroenterology defines constipation based upon symptoms including unsatisfactory defecation with either infrequent stools, difficult stool passage or both. Any recent change in bowel habits, if persistent, may be cause for concern.