Why is a body temperature measurement done?
Body temperature is measured to:
- Check for fever.
- Check for a very low body temperature in people who have been exposed to cold.
- Check for a very high body temperature in people who have been exposed to heat.
- Find out how well a fever-reducing medicine is working.
- Help a woman plan for pregnancy by finding out if she is ovulating.
How to take a forehead temperature
Before you take a temperature, read the instructions for how to use your type of thermometer.
Forehead thermometers aren't as accurate as electronic and ear thermometers. If your baby is younger than age 3 months or your child's fever rises higher than 102°F (39°C) , check the temperature again using a better method.
- Press the entire plastic strip firmly against a dry forehead.
- Hold the strip in place for the required amount of time.
Time yourself with a watch or clock.
- Read the temperature before removing the thermometer.
- Clean the thermometer with cool soapy water and rinse it off before you put it away.
How do you prepare for a body temperature measurement?
Take your temperature a few times when you are well. This will help you find out what is normal for you. Check your temperature in both the morning and evening. Body temperature can vary by as much as 1°F (0.6°C) during the day.
Before you take your temperature:
- Wait at least 20 to 30 minutes after you smoke, you eat, or you drink a hot or cold liquid.
- Wait at least an hour after hard exercise or a hot bath.
Glass thermometers that contain mercury aren't recommended. If you have a glass thermometer, contact your local health department to find out how to dispose of it safely. If you break a glass thermometer, call your local poison control center right away.
What do the results of a body temperature measurement mean?
If you tell your doctor about your temperature reading, be sure to say where it was taken: on the forehead or in the mouth, rectum, armpit, or ear.
Normal: | The average normal temperature is 98.6°F (37°C) . But that may not be normal for you. Your temperature also changes during the day. It is usually lowest in the early morning. It may rise as much as 1°F (0.6°C) in the early evening. Your temperature may also rise by 1°F (0.6°C) or more if you exercise on a hot day. A woman's body temperature often changes by 1°F (0.6°C) or more through her menstrual cycle. It peaks around the time she ovulates. |
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Abnormal: | Oral, ear, rectal, or temporal artery temperature
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| Armpit temperature
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| A rectal or ear temperature of less than 97°F (36.1°C) is a low body temperature (hypothermia). |
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