An umbilical hernia occurs when part of your intestine sticks out through the opening in your abdominal muscles through which your umbilical cord passed before you were born.Umbilical hernias that appear during adulthood are more likely to need surgical repair.In an infant, an umbilical hernia may be especially evident when the infant cries, causing the bellybutton to protrude.Umbilical hernias are common and typically harmless.This is a classic sign of an umbilical hernia.Children's umbilical hernias often close on their own in the first two years of life, though some remain open into the fifth year or longer.They are most common in infants, but they can affect adults as well.