Understanding Newborn Health: Rectal Temperature Basics

A newborn baby's temperature can be taken in several ways, including rectally, in the armpit, in the ear, on the forehead, or orally. Rectal temperatures are the most accurate way to take a newborn's temperature, and a normal rectal temperature for a newborn is 100.2°F or 37.9°C or lower. To take a rectal temperature, lubricate the tip of the thermometer with petroleum jelly, place your baby on their stomach on your lap or on their back with their legs pulled up to their chest, and gently insert the thermometer about half an inch into the rectum.

Rectal temperature readings are the most accurate for newborns

Taking a newborn's temperature is a crucial aspect of health monitoring, and rectal temperature readings are considered the most accurate method for newborns. Here's why rectal temperature readings are preferred and a step-by-step guide on how to perform them safely and effectively:

Accuracy and Reliability

Rectal temperature readings are highly accurate and reliable for newborns. While other methods such as armpit (axillary) temperatures are suitable for screening, they are not as precise as rectal measurements. Rectal temperatures provide a more direct measurement of core body temperature, making them the gold standard for newborns.

Step-by-Step Guide to Rectal Temperature Readings for Newborns:

• Prepare the Thermometer: Start by cleaning the thermometer with cool, soapy water, and then rinsing it thoroughly. Lubricate the tip of the thermometer with a small amount of lubricating jelly, following the manufacturer's recommendations on the type of jelly to use (water-soluble or petroleum-based).
• Position the Baby: Place your baby on a firm, flat surface, such as a changing table, or lay them on their stomach on your lap. Alternatively, you can hold them with their legs up near their ears while they are on their back. Ensure they are secure and comfortable.
• Insert the Thermometer: Using your hand, gently insert the lubricated thermometer through the anal opening. For newborns, insert it about half an inch (approximately 1.25 to 1.5 centimeters) into the rectum. Stop immediately if you feel any resistance.
• Steady the Thermometer: Hold the thermometer steady between your fingers, with your hand cupped gently against the baby's bottom. This helps keep the thermometer in place and provides comfort to the baby.
• Wait for the Reading: Continue holding the thermometer still until you hear the beep or signal indicating that the temperature reading is ready. Remove the thermometer and carefully read and record the temperature, noting the time of day for future reference.

Additional Tips:

• Always use a digital thermometer for rectal temperature readings, as recommended by the American Academy of Pediatrics (AAP).
• Clean the thermometer before and after each use to ensure hygiene and prevent the spread of any potential infections.
• Avoid taking your baby's temperature right after a bath or if they have been bundled tightly, as this can affect the accuracy of the reading.
• Never leave your baby unattended while taking their temperature.
• Remember that a fever is typically indicated by a rectal temperature of 100.4° F (38° C) or higher.

In summary, rectal temperature readings are the most accurate method for newborns, and following the above steps will help ensure a safe and effective temperature reading for your little one.

A newborn has a fever if their rectal temperature is 100.4° F or higher

A newborn baby's normal temperature is around 98.6° F. However, a rectal temperature of 100.4° F or higher is classified as a fever. A newborn with a fever may have an illness or infection, and it is recommended to seek medical attention, especially if the newborn is less than 3 months old.

To take a newborn's rectal temperature, you will need a digital thermometer. Lubricate the tip of the thermometer with petroleum jelly or a water-soluble jelly, following the manufacturer's instructions. Place your baby on their stomach on your lap or on their back with their legs pulled up to their chest. Gently insert the thermometer about half an inch to one inch into the rectum, stopping immediately if you feel any resistance. Hold the thermometer still and wait for it to beep before removing it and reading the temperature.

It is important to note that forehead temperature strips are not recommended as they do not provide accurate readings, especially in infants and children. Additionally, never use a mercury thermometer as it poses a risk of poisoning if it breaks.

If your newborn has a fever, it is important to keep them comfortable and offer plenty of fluids. Remove extra blankets and clothing to help lower their body temperature, but ensure they don't get too cold and start shivering, as this will raise their temperature again. In most cases, a fever means that your baby is fighting a cold, flu, or other viral or bacterial infection. However, a fever in the first 3 months of life can be a sign of a serious condition like sepsis or meningitis, so immediate medical attention is advised.

A rectal thermometer should be inserted about 1 inch into the rectum

Taking a newborn's temperature is a simple and safe process, and rectal temperatures are the most accurate way to do so. If your baby has had a bath or has been wrapped up warmly, wait 20-30 minutes before taking their temperature.

To take a rectal temperature, first, wash the end of the thermometer with soap and water and rinse it. Then, moisten the tip of the thermometer with a lubricant, such as petroleum jelly. Place your child either belly-down across your lap or on a firm, flat surface, keeping your palm along their lower back. You can also place them face-up with their legs bent toward their chest, with your hand against the back of their thighs.

With your other hand, insert the lubricated thermometer into the anal opening about 1/2 inch to 1 inch (1.25 to 2.5 centimetres), or until the tip of the thermometer is fully in the rectum. If your child is under six months old, insert it no more than 1/2 inch. If you feel any resistance, stop.

Steady the thermometer between your second and third fingers as you cup your hand against the child's bottom. Hold the thermometer still and soothe your child by speaking quietly until you hear the beeps indicating that the temperature is ready to be read. A reading of 100.4°F (38°C) or above means your child has a fever.

A newborn's armpit temperature reading should be 97.5 to 99.3° F

Taking a newborn's temperature is best done with a digital thermometer. Digital thermometers are inexpensive and can be purchased at any supermarket or pharmacy. They can be used to take both rectal and axillary (armpit) temperature readings. Rectal temperature readings are the most accurate way to take a newborn's temperature, but if this method makes you uncomfortable, taking an axillary temperature is the next best choice.

To take a rectal temperature, lubricate the tip of the thermometer with a lubricating jelly, following 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 (1.25 to 2.5 centimeters) into the rectum. If you feel any resistance, stop at less than 0.5 inches (1.25 centimeters). Steady the thermometer between your second and third fingers as you cup your hand against the baby's bottom. Wait until you hear the thermometer beep, then remove it and read the temperature.

To take an axillary temperature, remove the child's shirt and undershirt. Insert the thermometer into the child's armpit and fold their arm across their chest to hold the thermometer in place. Wait until the thermometer beeps, then remove it and read the temperature.

The normal temperature range for a newborn under the arm is 97.5 to 99.3° F (36.5 to 37.4° C). A rectal temperature of 100.2° F (37.9° C) or less is also considered normal. These are the American Academy of Pediatrics' recommended ranges. If you have any questions or concerns, be sure to discuss them with your baby's healthcare provider.

It's important to note that temperature strips placed on the forehead have been found to be poor indicators of true body temperature, especially in newborns and young children, and should be avoided. Additionally, never take your baby's temperature right after a bath or if they have been bundled tightly, as this can affect the reading.

A newborn with a fever should be taken to the doctor

A newborn baby's average body temperature is usually around 98.6 °F (37.0 °C) when taken orally, and 99.6 °F (37.6 °C) when taken rectally. A fever is typically diagnosed as a rectal temperature of 100.4 °F (38 °C) or higher.

Fever in newborns can be a sign of a serious infection, and it is crucial to act quickly. While fever is a normal part of the body's defense against infection, it can also indicate something more concerning, especially in very young infants.

If your newborn has a fever, there are several steps you should take:

• Take your newborn's temperature rectally, as this is the most accurate method for young babies.
• Contact your healthcare provider or paediatrician immediately and follow their instructions.
• Keep your newborn well-hydrated with breast milk or formula. Avoid giving fruit juice.
• Dress your newborn in lightweight clothing and avoid bundling them in too many layers or blankets, as this can trap heat and raise their body temperature further.
• Make sure the room is comfortable and not too hot or cold. A fan can help if the room is stuffy.
• You can give your newborn a lukewarm bath to help cool their body temperature. Avoid cold baths, ice, or alcohol rubs, as these can cause shivering and actually raise their temperature.
• Medications like acetaminophen (Tylenol) and ibuprofen (Advil, Motrin) can help lower a fever in children over 6 months old. However, always consult your doctor before giving any medication to a newborn, especially if they are under 3 months old.

It is important to trust your instincts as a parent. If you feel something is wrong or your newborn seems unwell, don't hesitate to seek medical advice.

Frequently asked questions