Hemorrhoids are caused by increased pressure in the lower part of the rectum, as reported by Mayo Clinic staff members. Several factors increase pressure in the lower rectum, including obesity, pregnancy and adherence to a low-fiber diet.
A hemorrhoid is a swollen vein in the anal canal, explains WebMD. External hemorrhoids swell outside the anus, while internal hemorrhoids swell near the anal opening.
Some people develop hemorrhoids because they spend too much time sitting on the toilet. Straining to have a bowel movement increases the risk for hemorrhoids, according to Mayo Clinic. Pregnancy contributes to the formation of hemorrhoids because of the pressure a developing fetus puts on a woman's pelvic area, as reported by WebMD.
Symptoms of a hemorrhoid include anal itching, bleeding without pain, swelling around the anus and irritation in the anal region. In some cases, hemorrhoids cause the leakage of fecal matter, as stated by Mayo Clinic. Anyone experiencing rectal bleeding should schedule an appointment with a doctor to rule out more serious medical problems. It is also important to seek medical care if a hemorrhoid bleeds excessively or causes excessive pain. Someone who experiences rectal bleeding accompanied by dizziness or faintness should go to the emergency room immediately.