Newborn Fevers: What You Need To Know

This content was reviewed and approved by Amanda Wilkins, MSN, RNC, IBCLC, LCCE
 
A fever is a body temperature of 100.4 degrees Fahrenheit or higher. It’s typically a sign that the immune system is fighting an illness and not something to be worried about unless it goes higher or lasts longer than your doctor feels it should.

However, fever in a baby under three months old is cause for concern, as it can be a sign of an infection that requires urgent medical treatment. This article provides information on fevers in newborns, including when and how to check a baby’s temperature.

What Can Cause a Fever in a Newborn?

Several conditions or circumstances can cause a baby to have a fever. The more serious include illnesses like meningitis and sepsis. Fevers can also be caused by cold or flu viruses, and urinary tract infections are common in girls.

Babies can even develop a fever from overheating in warm weather. Even so, fevers in babies should always be taken seriously.

When Should You Check Your Baby’s Temperature?

If your baby seems healthy and you don’t see any signs of illness, there’s no need to check their temperature. But you should monitor it if they have any of the following symptoms:

• Rapid breathing or trouble breathing
• Crying or fussing continually
• Poor sleeping
• Pale or yellow skin
• Cough
• Sore throat
• Rash or blotchy skin
• Sweating
• Vomiting (as opposed to normal spitting up)
• Shivering
• Stiff neck
• Convulsions or seizures
• Lack of appetite
• Decreased urination
• Seeming weak, tired or hard to wake
• Feeling warm to the touch

How To Take a Newborn’s Temperature

When taking a newborn’s temperature at home, pediatricians recommend using a digital thermometer under the baby’s arm (axillary method), as this method is generally safe, simple, and minimizes the risk of injury. Avoid taking temperatures orally, in the ear, or on the temple for newborns at home.

To safely and accurately measure your newborn’s temperature under the arm, follow these steps:

1. Ensure the digital thermometer is clean and dry.
2. Turn the thermometer on.
3. Place the thermometer tip securely in the center of your baby’s armpit, ensuring direct skin contact.
4. Gently hold your baby's arm against their side to keep the thermometer in place.
5. Wait until the thermometer beeps, indicating the measurement is complete.
6. Remove the thermometer and read the temperature.

A reading of 100.4 degrees Fahrenheit (38 degrees Celsius) or higher indicates a fever, and you should promptly contact your pediatrician.

Please note: Rectal temperature measurements should not be routinely performed at home due to potential injury risks. Only use the rectal method if specifically instructed by your pediatrician.

What To Do if Your Baby Has a Fever

If your baby is younger than two months and has a fever, you should immediately take them to an emergency department. If they are two months or older, call your baby’s primary care doctor right away.

Fever in a newborn can be a sign of severe illness. So, if you’re ever unsure about how to proceed, seek emergency care.

Talk With Your Baptist Health Pediatrician About Fevers in Newborns

If you have questions or concerns about your baby’s health, including how to respond if they develop a fever, your Baptist Health pediatrician can answer them. If you don’t have a doctor for your baby, you can find one using our online provider directory.

Next Steps and Helpful Resources

Learn more about Mother and Baby Care at Baptist Health
Baby Safety in the Summer Heat
7 Tips for Newborn Nail Care
Taking Care of Your Newborn