If your baby is under 3 months, even a mild temperature change can matter. Learn which newborn fever symptoms need a doctor, what counts as a fever, and when to seek urgent care.
Answer a few questions to get personalized guidance on whether your newborn’s temperature and symptoms suggest calling the pediatrician now, monitoring closely, or seeking urgent care.
For babies under 3 months, a rectal temperature of 100.4°F (38°C) or higher is generally considered a fever and is a reason to call a doctor right away. Newborns can get sick quickly, and fever may be one of the earliest signs of infection. Even if your baby does not seem very uncomfortable, it is important to take newborn fever warning signs seriously and get medical guidance promptly.
If your newborn is under 3 months and has a rectal temperature of 100.4°F or higher, call the doctor right away. This is one of the clearest signs for when to call the doctor for newborn fever.
If your baby is unusually sleepy, floppy, weak, or difficult to wake for feeds, newborn fever and lethargy together need prompt medical attention.
If your newborn has a fever and is feeding poorly, refusing feeds, vomiting repeatedly, or making fewer wet diapers, call the pediatrician as soon as possible.
When a newborn temperature reaches 100.4°F or higher, call your pediatrician the same day, even if your baby seems otherwise okay.
A newborn may need medical care even without a high fever if there is poor feeding, unusual fussiness, trouble breathing, or a clear change in behavior.
If you are not sure whether the reading is accurate, especially if it was not taken rectally, contact your doctor for guidance on next steps.
For newborns, rectal temperature is the most reliable way to confirm fever. Forehead, ear, or armpit readings can be less accurate in very young babies. If you got a borderline reading or are unsure whether your newborn fever over 100.4 means you should call the doctor, it is safest to check with your pediatrician and describe both the number and how the temperature was taken.
Fast breathing, grunting, pulling in at the ribs, or pauses in breathing are urgent warning signs, especially with fever.
Blue lips, pale or mottled skin, weak cry, or reduced responsiveness are signs to seek immediate medical care.
A spreading rash, repeated vomiting, or a baby who seems to be getting sicker rather than better should be evaluated promptly.
In a baby under 3 months, a rectal temperature of 100.4°F (38°C) or higher is considered a fever and is a reason to call a doctor right away.
Call your doctor promptly if your newborn under 3 months has a rectal temperature of 100.4°F or higher. Also call if your baby seems lethargic, is feeding poorly, has trouble breathing, or is difficult to wake.
Yes. If your newborn has a fever and is unusually sleepy, floppy, weak, or hard to wake, contact a doctor immediately. These are important newborn fever warning signs.
Yes. Newborn fever poor feeding when to call doctor is an important concern. If your baby is refusing feeds, taking much less than usual, or having fewer wet diapers, call your pediatrician promptly.
You should still call your pediatrician if your newborn seems unwell, especially with poor feeding, unusual fussiness, breathing changes, or low responsiveness. In very young babies, behavior changes can matter as much as the number on the thermometer.
Answer a few questions about your baby’s temperature, feeding, and behavior to get clear next-step guidance on whether to call the doctor now or seek urgent care.
Answer a Few QuestionsExplore more assessments in this topic group.
See related assessments across this category.
Find more parenting assessments by category and topic.
When To Call Doctor
When To Call Doctor
When To Call Doctor
When To Call Doctor