Haemorrhoids are painfully swollen blood vessels near a person’s anus — the opening where stool leaves the body. They can itch, ache, or bleed a little when you go to the toilet. Ordinary British speakers often say piles instead; doctors use both. They are very common, especially after sitting a long time, straining, or pregnancy, and people often feel shy talking about them. The trouble is usually not dangerous, though it can be miserable. British spelling is haemorrhoids; American spelling is hemorrhoids.