Necrotising enterocolitis (NEC)

Necrotising enterocolitis (NEC) is a serious condition that can affect newborn babies.

What is necrotising enterocolitis (NEC)?

Necrotising enterocolitis (NEC) is a serious condition that can affect newborn babies, where tissue in the bowel (small and large intestines) becomes inflamed. Doctors may also describe NEC as an inflammation of the gut.

NEC can affect just a small part of the bowel, or sometimes the whole bowel can be affected.

How serious is NEC?

NEC is a serious condition. Babies can become very unwell with NEC. Sometimes tissue in parts of the bowel will become damaged and die and will need to be removed with surgery. We have more information about surgery to treat NEC that you may find helpful.

Sadly, some babies will die of NEC. Some babies may be too unwell for surgery or may not get better with treatment. The healthcare professionals involved in your baby’s care should explain all the risks with any care they are providing. You can talk to them if you have any worries or concerns.

We have more information about making critical care decisions, palliative care and bereavement.

What causes NEC?

Doctors do not fully understand what causes NEC. Babies born premature or sick have more immature bowels, which means that they are more likely to get NEC than babies born healthy or term. It is likely that several factors are involved.

Who is most likely to get NEC?

NEC usually affects newborn babies in the first few weeks after birth. It is more common in:

  • premature babies, (particularly babies born before 32 weeks or who weigh less than 1500g)
  • babies who have a lot of other medical problems
  • babies who have been unwell before they were born (for example, babies who are not growing in the womb as expected).

NEC is most likely to affect babies before they go home from the neonatal unit.

NEC can also affect babies born at term and who have been otherwise well, although this is rare.

What are the signs of NEC?

NEC can be difficult for doctors to diagnose. But there are signs that a baby can show if they are becoming unwell with NEC. Doctors are likely to identify these signs in your baby on the neonatal unit.

Signs of NEC in your baby can include general signs of being unwell or fighting an infection, such as:

  • a fast heart rate
  • low blood pressure
  • irregular, fast, or slow and shallow breathing
  • a high, low or quickly changing temperature.

In some cases, more specific signs may develop, which may include:

  • not feeding as usual
  • blood in their stools (poo)
  • a painful, swollen or discoloured tummy
  • being sick (vomiting), especially if they are vomiting green liquid (bile)
  • having a large volume of green fluid, or blood coming back up your baby’s NG tube (if they are being fed by a tube).

If doctors think that your baby may have NEC, they will perform X-rays and blood tests. However, it can be hard to know if these signs are caused by NEC or other conditions.

You should always check with a healthcare professional if your baby is not being their usual self, or you think your baby is becoming unwell.

Sometimes a baby may become seriously unwell very quickly, and will need a lot of medical care. If you think your baby might be seriously unwell, alert healthcare professionals on the neonatal unit or call 999 if you are at home.

Can I reduce the risk of my baby getting NEC?

Research shows that breast milk can help reduce the risk of NEC. Most babies born premature will be unable to breastfeed in the first few weeks. If this happens, you may want to express your milk for your baby. This is then fed to them through a tube into their tummy. By doing this, your baby can still get the benefits of having your breast milk.

If your baby cannot take milk at this time but you want to feed your baby breast milk later on (either by breastfeeding or bottle feeding), you should continue to express breast milk. Using breast milk may also be helpful when your baby is recovering from NEC and is able to start milk feeds again. If you are finding it difficult to express breast milk, some units may have access to donor milk. Talk to staff at your unit for more information.

Healthcare professionals will be able to help you with feeding your baby. You can also visit our pages on feeding for more information.

What are the possible treatments for NEC?

If your baby has mild NEC, or healthcare professionals looking after your baby think your baby may have NEC, the following treatments may be started:

  • Stopping milk feeds. This is done because resting the bowel can help the bowel recover. When milk feeds cannot be given, your baby may be given nutrition, such as fat, sugar, protein and vitamins, through a long line. This is to make sure your baby grows while you are not feeding milk. A long line is a long, soft plastic tube inserted into a vein in your baby’s arm or leg.
  • Starting antibiotics to treat and prevent infections.

Other treatments may be needed if your baby becomes generally unwell, such as more oxygen or help with breathing. Many babies who have NEC recover with these treatments.

However, if an area of bowel dies, your baby doesn’t respond to treatment, or there is a perforation (hole) in the bowel, your baby will need surgery. We have more information about surgery to treat NEC that you may find helpful.

Your baby’s medical team should keep you aware of your baby’s care at all times, and you should be able to make decisions with them about your baby’s care.

What might happen after my baby has treatment for NEC?

Many babies who recover from NEC do not have further problems. But it is possible that other problems may develop.

These problems include the following:

  • NEC coming back (reoccurring). If this happens, your baby may need surgery. We have more information about surgery to treat NEC.
  • Strictures, which is where the bowel narrows because of scar tissue. This can be caused by damage to the bowel from NEC, or from surgery to treat NEC. If this happens, surgery will be needed to widen the area of bowel or possibly remove the narrow area.

Your baby may need surgery if any problems continue.

In the long term, some research shows that NEC can sometimes have an impact on how some babies’ brains develop. But all babies develop differently. Your baby’s development will be regularly assessed and monitored by healthcare professionals.