Taking Your Baby's Temperature (for Parents)
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Taking Your Baby's Temperature

It's bad enough that your baby is sick, but now you have to get him to stop squirming long enough to take his temperature. Of course, babies can't cooperate for an oral (in the mouth) temperature reading - so which method and what type of thermometer should you use?

Until recently, inexpensive glass mercury thermometers were the method of choice. But the American Academy of Pediatrics (AAP) now advises parents to stop using them at home because of concerns about possible exposure to mercury (an environmental toxin). If the thermometer should break, the mercury could leak out. Although the amount of mercury inside of a glass thermometer is actually very small, the AAP's official policy is that other types of thermometers are safer and have been found to be just as accurate in young children.

Your best bet these days is to use a digital thermometer (these can be bought inexpensively in any supermarket or pharmacy), which can be used to take rectal (in the bottom) or axillary (in the armpit) temperature readings. Taking a rectal temperature gives the most accurate reading of body temperature in infants and young children - but if the thought of it makes you squeamish, taking an axillary temperature is the next best choice.

Once your child is older than 3 months, a tympanic (ear) thermometer may also be used, although they are not as accurate (they tend to give falsely low readings in young children) and are not recommended by the AAP for young infants.

Be aware that temperature strips (which are placed upon someone's forehead to give a reading) have been found to be poor indicators of true body temperature, especially in infants and children, and should be avoided. The digital thermometer is best for temperature taking at home.

How to Take Your Baby's Temperature
When using a digital thermometer, read the directions beforehand so that you know which beep, or series of beeps, is a sign that the thermometer is finished taking a reading. Turn it on and make sure that the screen is clear of any old readings. If your thermometer uses disposable plastic sleeves or covers, place one on the thermometer. Remember to discard the sleeve after each use and to clean the thermometer according to the manufacturer's instructions before returning it to its case.

Taking a Rectal Temperature

  • Lubricate the tip of the thermometer with a lubricating jelly (check the manufacturer's directions to see whether water-soluble jelly or petroleum jelly is recommended).
  • Place your baby face down across your lap, supporting his head, or lie him down on a firm flat surface such as a changing table.
  • Press the palm of one hand firmly against your baby's lower back to hold him still.
  • Using your other hand, insert the lubricated thermometer through the anal opening, about 1/2 to 1 inch (about 1.25 to 2.5 centimeters) into the rectum. Stop at less than 1/2 inch (about 1.25 centimeters) if you feel any resistance.
  • Steady the thermometer between your second and third fingers as you cup your hand against your baby's bottom. Soothe your baby and speak to him quietly as you hold the thermometer in place.
  • Wait until you hear the appropriate number of beeps or other signal that the temperature is ready to be read. Read and record the number on the screen, noting the time of day that the reading was taken.

Taking an Axillary Temperature

  • Remove your child's shirt and undershirt (the thermometer should touch skin only, not clothing).
  • Insert the thermometer in your child's armpit. Fold your child's arm across his chest to hold the thermometer in place.
  • Wait until you hear the appropriate number of beeps or other signal that the temperature is ready to be read. Read and record the number on the screen, noting the time of day that the reading was taken.

Here are some additional tips to keep in mind:

  • Never take your baby's temperature right after he has had a bath or if he has been bundled tightly for awhile - this can affect the temperature reading.
  • Never leave a child unattended while taking his temperature.

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