What Causes Umbilical Hernia?

An umbilical hernia is an external abdominal hernia in which intra-abdominal contents protrude through a weak area at the umbilicus. In infants with umbilical hernia, a bulge—typically hemispherical or sac-like—appears at the navel. Several factors contribute to its development. Normally, after the umbilical cord is clamped and subsequently detaches, a scar forms at the umbilical site. During fetal development, the umbilical cord passes through the abdominal wall, which remains relatively weak at birth. Additionally, the rectus abdominis muscles on either side of the midline may not yet have fully fused along the linea alba, leaving a small gap. When intra-abdominal pressure increases, abdominal contents may thus protrude outward through this defect, resulting in an umbilical hernia.

Secondly, infants undergo rapid physical growth and development after birth. During feeding, they often swallow air, which may lead to choking or coughing. Crying further exacerbates abdominal distension and elevates intra-abdominal pressure. Because newborns have underdeveloped abdominal musculature and poor contraction of the umbilical ring, increased pressure can push the small intestine—along with the peritoneum and overlying abdominal skin—outward through the umbilical defect, thereby causing an umbilical hernia.

Timely treatment is essential following diagnosis of an umbilical hernia. In many cases, the condition improves spontaneously as the child grows older; however, deterioration may also occur, necessitating close monitoring and appropriate medical intervention.