A newborn’s body temperature is an important indicator of their overall health. Due to their delicate physiology, they are particularly susceptible to changes. Understanding what constitutes a fever in this age group and how to respond is important for parents.
Defining Fever in Newborns
While 99.5°F might not be a fever for an older child or adult, caution is important with newborns. For infants under three months old, a rectal temperature of 100.4°F (38°C) or higher is officially defined as a fever. This threshold is lower because a newborn’s immune system is still developing and is more susceptible to infections, so a fever can signal a serious underlying condition. Any fever in a newborn warrants immediate medical attention due to the potential for serious bacterial infections. Even a slight elevation, such as 99.5°F, warrants close monitoring and a call to a healthcare provider for guidance.
Proper Temperature Measurement Methods
The rectal method is the most reliable way to assess a newborn’s temperature, providing a measurement closest to the body’s core. To take a rectal temperature, clean a digital thermometer and apply a small amount of petroleum jelly to the tip. Position your baby on their belly across your lap with your hand on their lower back, or face-up with their legs lifted towards their chest. Gently insert the lubricated tip about 0.5 to 1 inch (1.25 to 2.5 centimeters) into the anal opening, stopping if you encounter any resistance. Hold the thermometer in place until it beeps, then remove it and read the temperature immediately.
Other temperature measurement methods, such as axillary (armpit), temporal artery (forehead), or tympanic (ear), are less accurate for newborns and should not be used as the primary indicator for fever. Axillary readings can be a preliminary check, but any elevated reading should be confirmed rectally. Temporal artery thermometers are less disturbing for newborns, but their accuracy can be influenced by external factors like sunlight or cold. Tympanic thermometers are not recommended for infants under six months due to potential inaccuracies caused by earwax or small ear canals. Always use a reliable digital thermometer and avoid mercury thermometers.
Immediate Steps for Newborn Fever
If a newborn, particularly one under three months of age, registers a rectal temperature of 100.4°F (38°C) or higher, contact their pediatrician or seek emergency medical attention without delay. This urgency is paramount because fever in a newborn can indicate a serious bacterial infection that requires prompt diagnosis and treatment. Be prepared to provide the medical team with specific details, including the exact temperature reading, the method used to take the temperature, any other symptoms observed, and information about the baby’s feeding habits and diaper output.
Avoid administering any fever-reducing medication to a newborn without direct medical instruction from a healthcare provider. Certain medications, like ibuprofen, are not recommended for infants under six months of age. Avoid home remedies such as cold baths, ice, or alcohol rubs, as these can cause shivering, which might actually increase the baby’s temperature, or lead to other harmful effects. Instead, keep the baby comfortable, ensuring they are not overdressed, and offering fluids like breast milk or formula to prevent dehydration.