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Hypoglycemia in a Newborn Baby

What is hypoglycemia in a newborn baby?

Hypoglycemia is when the level of sugar (glucose) in the blood is too low. Glucose is the main source of fuel for the brain and the body. In a newborn baby, low blood sugar can happen for many reasons. It can cause problems such as shakiness, blue tint to the skin, and breathing and feeding problems.

What causes hypoglycemia in a newborn baby?

Hypoglycemia can be caused by conditions such as:

  • Poor nutrition for the mother during pregnancy
  • Making too much insulin because the mother has poorly controlled diabetes
  • Incompatible blood types of mother and baby (severe hemolytic disease of the newborn)
  • Birth defects
  • Congenital metabolic diseases
  • Not enough oxygen at birth (birth asphyxia)
  • Liver disease
  • Infection

Which newborns are at risk for hypoglycemia?

Babies are more likely to have hypoglycemia include:

  • Babies born to mothers with diabetes
  • Babies who are small for gestational age or growth-restricted
  • Preterm babies, especially those with low birth weights
  • Babies born under significant stress
  • Babies with mothers treated with certain medicines such as terbutaline
  • Babies who are large for their gestational age

What are the symptoms of hypoglycemia in a newborn baby?

Signs of low blood sugar may not be obvious in newborn babies. The most common signs include:

  • Shakiness
  • Blue tint to skin and lips (cyanosis)
  • Stopping breathing (apnea)
  • Low body temperature (hypothermia)
  • Floppy muscles (poor muscle tone)
  • Not interested in feeding
  • Lack of movement and energy (lethargy)
  • Seizures

The signs of hypoglycemia can be like other health conditions. Make sure your child sees his or her healthcare provider for a diagnosis.

How is hypoglycemia in a newborn baby diagnosed?

A simple blood test for blood glucose levels can diagnose the problem.

How is hypoglycemia in a newborn baby treated?

Treatment will depend on your baby's gestational age and overall health. Treatment includes giving the baby a fast-acting source of glucose. This may be as simple as a glucose and water mixture or formula as an early feeding. Or your baby may need glucose given through an IV. The baby's blood glucose levels are checked after treatment to see if the hypoglycemia occurs again.

What are possible complications of hypoglycemia in a newborn baby?

The brain needs blood glucose to function. Not enough glucose can harm the brain's ability to function. Severe or long-lasting hypoglycemia may cause seizures and serious brain injury.

Can hypoglycemia in a newborn baby be prevented?

In many cases, there may not be a way to prevent hypoglycemia in a newborn baby. For a baby with risk factors, healthcare providers will need to watch carefully for the signs and treat as soon as possible. Mothers with diabetes should keep their blood glucose levels in a normal range during pregnancy. This may help lower the risk for their baby.

When should I call my child's healthcare provider?

Call your baby’s healthcare provider right away you see signs of low blood sugar in your baby. Give your baby formula or a glucose and water mixture, if advised.

Key points about hypoglycemia in a newborn baby

  • Hypoglycemia is a condition in which the level of glucose in the blood is lower than normal.
  • A baby is at risk if he or she has a mother with diabetes, is preterm, or is large.
  • If your baby has signs of hypoglycemia, give him or her formula or glucose and water mixture.

Next steps

Tips to help you get the most from a visit to your child’s health care provider:
  • Before your visit, write down questions you want answered.
  • At the visit, write down the names of new medicines, treatments, or tests, and any new instructions your provider gives you for your child.
  • If your child has a follow-up appointment, write down the date, time, and purpose for that visit.
  • Know how you can contact your child’s provider after office hours. This is important if your child becomes ill and you have questions or need advice.

Medical Reviewers:

  • Freeborn, Donna, PhD, CNM, FNP
  • Goode, Paula, RN, BSN, MSN