How to take a newborn’s temperature

How to take a newborn’s temperature

Your best bet is to use a digital thermometer. These can be bought inexpensively in any supermarket or pharmacy and 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. However, if the thought of doing this makes you squeamish, taking an axillary temperature is the next best choice.

Be aware that temperature strips, which are placed on someone's forehead for 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.

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 on a firm, flat surface such as a changing table.
  • Using your hand, insert the lubricated thermometer through the anal opening, about one-half to one inch or about 1.25 to 2.5 centimeters into the rectum. Stop at less than ½ inch or 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/her 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.

Additional tips

  • Never take your baby's temperature right after a bath or if he/she has been bundled tightly for a while — this can affect the temperature reading.
  • Never leave a child unattended while taking his temperature.
  • Temperature should be taken only if the baby feels hot or is lethargic.
  • A baby's normal temperature range:
    • Under the arm is 97.5 to 99.3 degrees Fahrenheit or 36.5 to 37.4 degrees Celsius.
    • Rectal is 100.2 degrees Fahrenheit or less, or 37.9 degrees Celsius or less.
  • These are the American Academy of Pediatrics recommended ranges. If you have questions or concerns, be sure to discuss them with your baby's healthcare provider

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