Neonatal Hypoglycaemia

Glucose is the major source of energy for foetus and neonate. When glucose demands are increased or when glucose supply is limited, a child becomes susceptible to hypoglycaemia. A severe or prolonged hypoglycaemia may result in long term damage to the nervous system.

Definition

Low blood sugar levels in new-born babies are also called neonatal hypoglycaemia.

In most of the cases, it is easily treatable but in some instances can have serious consequences.

Causes, incidence, and risk factors

Infants with low blood sugar may not have symptoms. After birth, nurses in the hospital will check your baby's blood sugar levels, even if there are no symptoms.

Babies need blood sugar (glucose) for energy. Most of that glucose is used by the brain.

The baby gets glucose from the mother through the placenta before birth. After birth, the baby gets glucose from the mother through her milk or from formula, and also produces it in the liver.

Glucose levels can drop if:

  • There is too much insulin in the blood (hyperinsulinism)
  • The baby is not producing enough glucose
  • The baby's body is using more glucose than is being produced
  • The baby is not able to feed enough to keep glucose levels up

Neonatal hypoglycaemia occurs when the new-born’s glucose level is below the level considered safe for the baby's age. It occurs in about 1 to 3 out of every 1,000 births.

Low blood sugar levels are more likely in infants:

  • Who were born early, have a serious infection, or needed oxygen right after delivery
  • Whose mother has diabetes (These infants are often larger than normal.)
  • With low thyroid hormone levels (hypothyroidism)
  • Who have certain rare genetic disorders
  • Who have poor growth in the womb during pregnancy
  • Who are smaller in size than normal for their gestational age

Tests

New-borns at risk for hypoglycaemia should have a blood test to measure blood sugar levels every few hours after birth. This will be done using a heel stick. The health care provider should continue taking blood tests until the baby’s glucose level stays normal.

Other possible tests:

  • New-born screening for metabolic disorders
  • Urine tests

Treatment

Infants with low blood sugar levels will need to receive extra feedings with breast milk or formula. Babies who are breastfed may need to receive extra formula until the mother is able to produce enough breast milk.

The baby may need a sugar solution given through a vein (intravenously) if he or she is unable to eat by mouth, or if the blood sugar is very low.

Treatment will be continued for a few hours or days to a week, or until the baby can maintain blood sugar levels. Infants who were born early, have an infection, or were born at a low weight may need to be treated for a longer period of time.

If the low blood sugar continues, in rare cases, the baby may also receive medication to increase blood sugar levels. In very rare cases, new-borns with very severe hypoglycaemia who don't improve with treatment may need surgery to remove part of the pancreas (to reduce insulin production).

When to call your Doctor:

If they do occur, symptoms may include:

  • Bluish-coloured or pale skin
  • Breathing problems, such as pauses in breathing (apnoea), rapid breathing, or a grunting sound
  • Irritability or listlessness
  • Loose or floppy muscles
  • Poor feeding or vomiting
  • Problems keeping the body warm
  • Tremors, shakiness, sweating, or seizures