Groin hernia affects 2–3% of the population, mostly men (at a ratio of four to one). The most common place for hernia to occur (in males) is the inguinal canal, because this is where the testes descend from the abdominal cavity. There are two types of groin hernia: indirect or congenital and direct or acquired. The latter is usually caused by increased pressure, as produced by heavy lifting. Hernia can also occur on both sides of the groin. The first symptom of groin hernia is pain in the lower abdomen or groin when lifting or straining. Another possible symptom is a bulge, which commonly disappears on lying down.