Everyone has swellings in the anal canal (back passage) called anal cushions. These bulges in the lining of the anal canal act like the washer on a tap and help prevent leaks from the back passage and maintain continence. Over time these swellings can lose their normal structure and become stretched. This can cause them to bleed, or protrude outside the anus (prolapse). When this happens they are called haemorrhoids, or piles. This can lead to symptoms including bleeding, discomfort, itching and a feeling of incomplete emptying. It is not known why some people suffer from haemorrhoids and others do not. There is an association with constipation and straining, but they can be associated with a normal bowel habit. They are more common in some families, and during or after pregnancy. Up to one in three people will suffer from haemorrhoids during their lifetime. There are a number of different treatments. Banding is sometimes helpful for more minor degrees of haemorrhoids.