An umbilical hernia occurs when part of the bowel or fatty tissue pokes through an area near the belly button, pushing through a weak spot in the surrounding abdominal wall.
They are common in newborns and infants, but they can affect adults, too.
Although umbilical hernias are easily treatable, they can become a serious condition on rare occasions.
This article looks at the causes, risk factors, diagnosis, and treatment of umbilical hernias.
Fast facts on umbilical hernia
- Umbilical hernias are common in babies born preterm.
- They are not normally painful, but if they become sore, a doctor should be consulted.
- Obesity is a risk factor for umbilical hernias.
- Diagnosis of an umbilical hernia can normally be confirmed by a physical examination alone.
Umbilical hernias are common in young infants, but the exact rate is not known because many cases go unreported and resolve themselves without the need for treatment.
They are particularly common in infants born preterm. Up to 75 percent of newborns with a birth weight of less than 1.5 kilograms (kg) have an umbilical hernia.
While the developing fetus is in the womb, the umbilical cord passes through an opening in the abdominal wall. This should close soon after birth.
However, the muscles do not always seal completely, leaving a weak spot through which an umbilical hernia can push.
In most cases, an umbilical hernia experienced by an infant closes on its own by the age of 3 to 4 years. If a hernia is still present by the time the child is 4 years old, a doctor may recommend surgery.
Umbilical hernias can also develop in adults, especially if they are clinically overweight, lifting heavy objects, or have a persistent cough. Women who have had multiple pregnancies have a higher risk of developing an umbilical hernia.
In adults, hernias are much more common in females. Among infants, the risk is about the same for males and females.
An umbilical hernia looks like a lump in the navel. It might become more obvious when the infant is laughing, crying, going to the toilet, or coughing. When the child is lying down or relaxed, the lump may shrink.
It is not usually painful in children and infants. However, adults may feel pain or discomfort if a hernia is large.
When to see a doctor:
Visit a physician in the following cases:
- The bulge becomes painful.
- Vomiting occurs, accompanied by a bulge.
- The bulge swells up more or becomes discolored.
- You used to be able to push the bulge flat against the abdomen, but now it cannot be reduced without significant pain or tenderness.
The major risk factors for umbilical hernias are:
- Age: Infants, especially those born preterm, have a higher risk of an umbilical hernia than adults.
- Obesity: Children and adults with obesity face a significantly higher risk of developing an umbilical hernia, compared with individuals of normal weight for their height and age.
- Coughing: Having a cough for a long period of time can increase the risk of hernias, because the force of coughing applies pressure to the abdominal wall.
- Multiple pregnancies: When a woman is carrying more than one baby as part of a pregnancy, the risk of an umbilical hernia is higher.
The causes of umbilical hernia are different across age groups.
Infants: As the fetus develops in the womb, a small opening forms in the abdominal muscles. This opening allows the umbilical cord to pass through. This connects the woman who is pregnant to the baby.
Around the time of birth, or shortly after, the opening should close. If this does not happen completely, fatty tissue or part of the bowel can poke through, causing an umbilical hernia.
Adults: If there is too much pressure on the abdominal wall, fatty tissue or a part of the bowel can poke through a weak section of abdominal muscle. Individuals at high risk are more likely to experience higher-than-normal pressure in areas where fatty tissue or parts of the gut can protrude.
A doctor will be able to diagnose an umbilical hernia during a physical examination. They may also be able to determine what type of hernia is it. If it involves the bowel, for example, there may be a risk of obstruction.
If the doctor wants to screen for complications, they may request an abdominal ultrasound, X-ray, or blood tests.
Treatment is not always required, as some instances of umbilical hernia self-resolve. However, this may not always be the case, especially for adults.
Infants and children: For the majority of infants, the hernia closes without treatment by the age of 12 months. Sometimes, the doctor may be able to push the lump back into the abdomen. It is important that only the doctor attempts this.
Surgery may be requested if:
- the hernia grows after the child is 1 to 2 years old
- the bulge is still present by the age of 4 years
- the intestines are within the hernial sac, preventing or reducing intestinal movement
- a hernia becomes trapped
Adults: Surgery is usually recommended for adults. This can prevent potential complications, especially if the hernia grows or starts to hurt.
Umbilical hernia surgery is a small, quick operation to push the bulge back into place and to strengthen the abdominal wall.
In most cases, the person receiving surgery will be able to go home on the same day.
According to the American College of Surgeons, either open or laparoscopic surgery may be used.
Surgery involves makes an incision at the base of the bellybutton and pushes either the fatty lump or bowel back into the abdomen.
In open surgery, the surgeon will open the site and repair the hernia by using mesh and stitching the muscle together.
In laparoscopic surgery, or keyhole, surgery, mesh and sutures will be pass through small incisions.
Muscle layers are stitched over the weak area in the abdomen wall, fortifying it.
Dissolvable stitches or special glue are used to close the wound. The surgeon will sometimes apply a pressure dressing on the hernia, which remains in place for 4 to 5 days.
An umbilical hernia operation usually takes about 20 to 30 minutes.
Complications of umbilical hernia are rare in children.
If the protrusion becomes trapped and cannot be pushed back into the abdominal cavity, the primary concern is that the intestines might lose blood supply and become damaged.
If the blood supply is completely cut off, there is a risk of gangrene and life-threatening infections. Incarceration is rare in adults and even less common in children.