How should I take my newborn's temperature?

To take a newborn’s temperature use a digital thermometer. Glass thermometers are a potential danger to newborns because of the mercury they contain.

The best ways to take a temperature in a newborn are rectal and axillary. Because babies may have fluid in their ears, wait until the baby is over three months of age before using an ear thermometer. Oral temperatures are usually not use in children until they are 4-5 years old and able to follow directions and be cooperative.

A rectal temperature us the most accurate measure of the newborn’s core or body temperature. Using a clean, digital thermometer, coat the end with a small amount of water soluble lubricant. Place the baby across your lap or on the changing table with the legs in the air. Turn on the thermometer and slowly insert it into the rectum, no further than ½ inch. Hold the thermometer in place to prevent injury. When it beeps, remove it and note the temperature. Clean the thermometer with alcohol before putting it away.

An axillary temperature is easier to take, but not as accurate as a rectal temperature. To take an axillary temperature remove the baby’s shirt and make sure the underarm area is dry. Hold or position the baby securely and place the tip of the thermometer into the pit of the axilla. Hold the baby’s arm snuggly to the side of the body to stabilize the thermometer. When the thermometer beeps, remove it and note the temperature. Clean the thermometer before putting it away.

Rectal temperatures are the most accurate and preferred method in newborns. Although the idea may seem uncomfortable to you, it won’t hurt your baby.

Just coat the end of the thermometer with a lubricant (such as water-based K-Y Jelly or petroleum-based Vaseline) and insert about half an inch (follow the instructions for your particular thermometer).

Digital thermometers provide a quick, fairly accurate reading—within a minute you’ll know your baby’s temperature.

If the thermometer reads 100.4°F (38°C) or higher, your newborn has a fever, which may sometimes indicate a serious infection.

Although most newborn fevers are not serious, little ones can get very sick very quickly and should be evaluated as soon as possible—even if it means a trip to the emergency department in the middle of the night!

Find out more about this book: Mommy Calls: Dr. Tanya Answers Parents' Top 101 Questions About Babies and...

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