Constipation is considered to be one of the most common hemorrhoids causes. It is a known fact that constipation typically causes lot of discomfort during bowel movement. The reason being the stools have become very hard and so it becomes very difficult to remove them from the rectum. The constipated person has to really put a lot of pressure on the lower part of intestine in order to push fecal matter out of the body. This straining during bowel movement is bound to cause the veins to swell. Of course, feeling constipated just once or twice doesn't immediately cause hemorrhoids. The inflammation of the veins in the anus is usually the result of chronic constipation. Once hemorrhoids develop especially in the inside region of the anus, one experiences pain in the affected area ever time the person goes to the toilet for bowel evacuation.