Blood Glucose - Hypoglycemia

What is hypoglycemia?
Hypoglycemia is a condition in which the amount of blood glucose (sugar) in the blood is lower than normal. ]

Glucose–a vital fuel
Found in foods, glucose is an important source of immediate energy for the body. Glucose can also be stored as other forms in the liver and muscles for later use. Excess glucose is converted to fat.

Glucose is the main source of fuel for the brain, and is especially important for babies and young children. Complex hormonal and neurologic mechanisms regulate the amount of glucose between meals.

During pregnancy, glucose is passed to the fetus from the mother through the placenta. Some of the glucose is stored as glycogen in the placenta and later, in the fetal liver, heart, and muscles. These stores are important for supplying the baby's brain with glucose during delivery, and for nutrition after the baby is born.

What causes hypoglycemia?
Hypoglycemia may be caused by conditions that:

  • Lower the amount of glucose in the bloodstream.
  • Prevent or lessen storage of glucose.
  • Use up glycogen stores (sugar stored in the liver).
  • Inhibit the use of glucose by the body.

Many different conditions are associated with hypoglycemia, including the following:

  • Inadequate maternal nutrition in pregnancy.
  • Excess insulin produced in a baby of a diabetic mother.
  • Severe hemolytic disease of the newborn (incompatibility of blood types of mother and baby).
  • Birth defects and congenital metabolic diseases.
  • Birth asphyxia.
  • Cold stress (conditions that are too cold).
  • Liver disease.


Who is affected by hypoglycemia?
Approximately two out of 1,000 newborn babies have hypoglycemia. Babies who are more likely to develop hypoglycemia include:

  • Babies born to diabetic mothers may develop hypoglycemia after delivery when the source of glucose (the mother's blood) is gone and the baby's insulin production metabolizes the existing glucose.
  • Small for gestational age or growth-restricted babies may have too few glycogen stores.
  • Premature babies, especially those with low birthweights, who often have limited glycogen stores (sugar stored in the liver) or an immature liver function.

Why is hypoglycemia a concern?
The brain depends on blood glucose as its main source of fuel. Too little glucose can impair the brain's ability to function. Severe or prolonged hypoglycemia may result in seizures and serious brain injury.

What are the symptoms of hypoglycemia?
Symptoms of hypoglycemia may not be obvious in newborn babies. The following are the most common symptoms of hypoglycemia. However, each baby may experience symptoms differently. Symptoms may include:

  • Jitteriness.
  • Cyanosis (blue coloring).
  • Apnea (stopping breathing).
  • Hypothermia (low body temperature).
  • Poor body tone.
  • Poor feeding.
  • Lethargy.
  • Seizures.

The symptoms of hypoglycemia may resemble other conditions or medical problems. Always consult your baby's physician for a diagnosis.

How is hypoglycemia diagnosed?
A simple blood test for blood glucose levels can diagnose hypoglycemia. Blood may be drawn from a heel stick, with a needle from the baby's arm, or through an umbilical catheter (a tube placed in the baby's umbilical cord). Generally, a baby with low blood glucose levels will need treatment.

Treatment for hypoglycemia:
Specific treatment for hypoglycemia will be determined by your baby's physician based on:
  • Your baby's gestational age, overall health and medical history.
  • Extent of the disease.
  • Your baby's tolerance for specific medications, procedures or therapies.
  • Expectations for the course of the disease.
  • Your opinion or preference.

Treatment includes giving the baby a rapid-acting source of glucose. This may be as simple as giving a glucose/water mixture or formula as an early feeding. Or, the baby may need glucose given intravenously. The baby's blood glucose levels are closely monitored after treatment to see if the hypoglycemia occurs again.

Prevention of hypoglycemia:

There may not be any way to prevent hypoglycemia, only to watch carefully for the symptoms and treat as soon as possible. Mothers with diabetes with blood glucose levels in tight control can help minimize the amount of glucose that goes to the fetus.

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