Hernia: Causes

What causes a hernia?

The cause of a hernia depends on the type of hernia. In some cases, a hernia can be due to a congenital (present at birth) defect; whereas, in other cases, certain risk factors have been documented but the underlying cause is not known.

Hiatal hernia

A hiatal hernia is the protrusion of a portion of the stomach through an opening in the diaphragm. A hiatal hernia can be caused by an unusually large hiatus, which is a hole in the diaphragm through which the esophagus passes into the stomach. In most cases, the cause of hiatal hernia is unknown, but the likelihood of developing a hiatal hernia increases with age and other factors.

Inguinal hernia

The cause of an inguinal hernia depends on whether it is a congenital inguinal hernia (present at birth) or a direct inguinal hernia, which occurs later in infancy, childhood or adulthood. Congenital (or indirect inguinal) hernia is caused when the opening to the inguinal canal does not close properly during fetal development, leaving an area in the abdominal wall susceptible to rupturing. Direct inguinal hernias are caused by weakening or deterioration of the abdominal muscles over time and can be made worse by such activities as heavy lifting, straining during bowel movements, and coughing.

Umbilical hernia

Umbilical hernias occur when the abdominal muscles through which the umbilical cord passes during fetal development do not close properly just after birth. If the muscles do not close properly, part of the intestines can push through the opening.

Congenital diaphragmatic hernia

Congenital diaphragmatic hernias are formed when the diaphragm, diaphragmatic tendons, or digestive tract does not grow properly during fetal development. In some cases, a congenital diaphragmatic hernia is a feature of a genetic or chromosomal disorder such as Donnai-Barrow syndrome, Fryns syndrome, or Pallister-Killian mosaic syndrome. But in most cases, the underlying cause of congenital diaphragmatic hernia is unknown.

What are the risk factors for a hernia?

A number of factors increase the risk of developing different types of hernia. Not all people with risk factors will develop a hernia.

Risk factors for hiatal hernia

Risk factors for hiatal hernia include:

• Age 50 years or older

• Obesity

• Pregnancy and delivery

• Smoking

Risk factors for inguinal or femoral hernia

Risk factors for an inguinal or femoral hernia include:

• Age 50 years or older (for femoral hernia)

• Chronic cough or constipation (causing you to strain during bowel movements)

• Family history of inguinal or femoral hernia

• Female gender

• Large amount of time spent standing up or lifting heavy items

• Male gender (for inguinal hernia)

• Obesity

• Pregnancy

• Premature birth

Risk factors for umbilical hernia

Risk factors for an umbilical hernia include:

• African American ethnicity

• Beckwith-Wiedemann syndrome

• Down syndrome

• Low birth weight or premature birth

• Mucopolysaccharidoses (inherited metabolic disorder)

Risk factors for congenital diaphragmatic hernia

The only known risk factor for congenital diaphragmatic hernia is having a parent or sibling born with a congenital diaphragmatic hernia.