When an organ residing in a cavity such as the abdomen tries to push through the muscular layer it resides, it is called as hernia.

Though said to be genetic, hernias can be caused by things such as improper heavy lifting, incorrect posture, or chronic constipation and as a result of surgical complication or injury. Factors like obesity, pregnancy, smoking, chronic lung disease aggravate the severity of the hernia. It is believed that about 27% of all males and 3% of females can have a hernia during their lifetime.

Types of hernias:

Inguinal hernia - The groin is the most common area, where the abdomen pushes through a weak spot in the lower abdominal wall, causing a protrusion into the inguinal canal. More common in men than women.

Hiatal hernia - The abdomen has the diaphragm separating it from the thoracic cavity in the upper border. When it pushes through the diaphragm, a hernia is caused and there is almost always associated food reflux in these cases. Though the most common cause is associated old age, due to muscle weakness, there also are cases of congenital hiatal hernias.

Umbilical hernia - The abdomen finds a weak layer along its length and protrudes through the skin on the stomach. Most commonly seen in babies around the bellybutton, it gradually corrects itself on its own. Quiet rare in adults, seen during pregnancy and in chronic obese people.

Incisional - These are post-surgical, and happen when the organ protrudes through the weakened wall due to surgery. The abdomen is again the most common area and the hernia can happen either onto the external surface or internally, when they are called ventral hernias.
These are the most frequent types, though hernia affects other organs like the spine, brain, appendix, etc.

Treatment - This includes a combination of constant monitoring followed by a decision to do surgical treatment. Hiatal hernias and umbilical hernias can be monitored for a while before deciding on surgery. Inguinal hernias may require surgery earlier in the stage. Post-surgery, a mesh is placed to hold back the tissue in its corrected place. The umbilical hernia in children could be self-limiting. If it does not get auto-corrected in the first year of life, that also would qualify for a surgical treatment.

Dependent on each patient, hernias need to be managed under medical supervision.