How to Take a Rectal Temperature
The most accurate way to measure temperature in infants and young children
📊Why Rectal Temperature?
The rectal method is the most accurate way to take a temperature in infants and young children. It provides the most reliable reading, which is especially important when you need to know if your baby truly has a fever.
When to Use Rectal Temperature:
- ✓Infants 0-3 months: Always use rectal method (most accurate for young babies)
- ✓Infants 3-6 months: Rectal method recommended for accuracy
- ✓Young children: Can use until about age 3 if tolerated
- ✓When accuracy is critical: Any time you need the most precise reading
🛠️What You'll Need
📋Required Items
- •Digital thermometer (not glass!)
- •Lubricant (petroleum jelly or water-based)
- •Clean cloth or tissue
- •Soap and water for cleaning
⚠️Important Safety Notes
- ✗Never use glass mercury thermometers
- ✓Use digital thermometers only
- ✓Label for "rectal use only"
- ✓Keep separate from oral thermometers
📝Before You Begin
Wait if Your Baby Has:
- • Been bathed recently (wait 20-30 minutes)
- • Been under blankets or swaddled (wait 20-30 minutes)
- • Been in multiple layers of clothing (wait 20-30 minutes)
These can artificially raise body temperature and give inaccurate readings.
Preparation Steps:
- 1.Wash the thermometer end with soap and water, then rinse
- 2.Moisten the tip with lubricant (petroleum jelly works well)
- 3.Gather all supplies and find a comfortable, well-lit space
- 4.Wash your hands thoroughly
👣Step-by-Step Instructions
Position Your Child
Choose one of these positions:
Option A: Belly-Down
- • Place baby across your lap
- • Or on firm, flat surface
- • Keep your palm on lower back
- • This position works well for most babies
Option B: Face-Up
- • Lay baby on back
- • Bend legs toward chest
- • Hold back of thighs with one hand
- • Good for squirmy babies
Insert the Thermometer
- •Gently insert the lubricated thermometer into the anal opening
- •Insert only ½ inch to 1 inch (about 1.25 to 2.5 centimeters)
- •Insert until the tip is fully in the rectum
- ⚠️STOP if you feel any resistance - never force it
Important:
The thermometer should slide in easily with the lubricant. If it doesn't, stop and try a different method or call your doctor.
Hold Steady and Comfort
- •Steady the thermometer between your second and third fingers
- •Cup your hand against your child's bottom
- •Hold the thermometer in place - don't let go
- •Soothe your child and speak quietly while holding
Comfort Tips:
- • Talk or sing softly to your baby
- • Make eye contact and smile
- • Stay calm - babies can sense your stress
- • Have a favorite toy ready for distraction
Wait for the Reading
- •Wait until you hear the beeps or signal (usually 20-30 seconds)
- •Gently remove the thermometer
- •Read the temperature on the screen
- •Write down the number and the time
Clean and Store
- •Wash the thermometer thoroughly with soap and water
- •You can also clean with rubbing alcohol
- •Label it clearly for "RECTAL USE ONLY"
- •Store separately from oral thermometers
📊Understanding the Reading
A rectal temperature reading of 100.4°F (38°C) or higher is considered a fever.
Normal
Below 100.4°F
(38°C)
Low Fever
100.4-102°F
(38-38.9°C)
High Fever
Above 102°F
(38.9°C)
🚨Call Doctor Immediately If:
- Baby under 3 months: ANY fever of 100.4°F (38°C) or higher
- Baby 3-6 months: Temperature above 102°F (38.9°C)
- Any age: Fever with lethargy, difficulty breathing, or other concerning symptoms
💡Tips for Success
✓Do:
- • Stay calm and confident
- • Use plenty of lubricant
- • Be gentle and patient
- • Keep the thermometer steady
- • Comfort your baby throughout
- • Record the temperature and time
✗Don't:
- • Force the thermometer if there's resistance
- • Insert more than 1 inch
- • Let go of the thermometer
- • Rush the process
- • Use glass thermometers
- • Reuse oral thermometer rectally
🔄When to Use Other Methods
While rectal temperature is most accurate for young children, other methods may be appropriate:
Related Topics
ℹ️Medical Note
This information is for educational purposes. If you're uncomfortable taking a rectal temperature or if your child resists strongly, ask your pediatrician about alternative methods.
Always contact your doctor if your infant under 3 months has any fever, or if you have concerns about your child's temperature or symptoms.