The Playbook

When to Call the Pediatrician About Your Newborn: A Dad's Checklist

Fever of 100.4°F in a baby under 3 months, breathing trouble, poor feeding, few wet diapers, jaundice and more: when to call the pediatrician and when to call 911.

By the Guide to Fatherhood editorial team. Last reviewed . 2 min read.

Checked against guidance from organizations like the AAP, CDC, ACOG and NHS (linked below). This is general information, not medical advice. Read our medical disclaimer.

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New parents call the pediatrician a lot, and they should. Save the pediatrician’s number and the after-hours or nurse line in your phone before the baby comes home. This checklist covers the situations where you shouldn’t wait.

This is general information, not a diagnosis. If your gut says something is wrong, call. If you think it’s an emergency, call 911.

Call 911 right away

  • The baby is not breathing, is turning blue or gray around the lips, or is struggling hard to breathe.
  • The baby is limp, unresponsive, or can’t be woken.
  • The baby has a seizure.
  • There’s severe bleeding or a serious injury, including any fall or blow to the head with vomiting, unusual sleepiness, or a change in behavior.

Call the pediatrician right away

Fever in a baby under 3 months

A rectal temperature of 100.4°F (38°C) or higher in a baby younger than 3 months needs a call to the pediatrician right away, even if the baby seems fine (AAP). Young babies can get serious infections with few other symptoms. Don’t give fever medicine before talking to the doctor.

Also call if a newborn’s temperature is unusually low; ask your pediatrician at the first visit what number should prompt a call.

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Breathing

Fast breathing, grunting with each breath, flaring nostrils, or the skin pulling in between the ribs with each breath.

Feeding and diapers

  • Refusing to feed, or feeding much less than usual.
  • Fewer wet diapers than your pediatrician said to expect, dark urine, a dry mouth, or a sunken soft spot (signs of dehydration).
  • Repeated forceful vomiting, or green or bloody vomit.
  • Blood in the stool, or white, gray, or very pale stools.

Skin and color

  • Jaundice (yellow skin or eyes) that’s spreading to the belly or legs, deepening, or comes with poor feeding or unusual sleepiness (AAP).
  • A rash with fever, or small purple-red spots that don’t fade when pressed.
  • Redness, swelling, pus or a bad smell around the umbilical stump or circumcision.

Behavior

  • Unusual sleepiness, hard to wake for feeds, or floppy.
  • Inconsolable crying that sounds different (high-pitched or weak), or crying with other symptoms.
  • Extreme irritability.

Call during office hours

  • Mild diaper rash that isn’t improving after a few days.
  • Questions about feeding amounts, spit-up, sleep, or stools.
  • A cold with a stuffy nose that’s making feeding harder.
  • Anything you’re unsure about.

How to make the call useful

Have this ready:

  • The baby’s age, and temperature (and how you took it).
  • What you noticed and when it started.
  • Feeds and diapers in the last 24 hours.
  • Any medicines given.

Write down what the nurse or doctor tells you to do and when to call back. Then follow up if things change.

Frequently asked questions

What temperature is a fever in a newborn?

A rectal temperature of 100.4°F (38°C) or higher. For babies younger than 3 months, the AAP says to call the pediatrician right away, even if the baby seems fine otherwise.

Should I take my newborn's temperature rectally?

For babies under 3 months, a rectal temperature with a digital thermometer is considered the most accurate. Use a little petroleum jelly and insert the tip gently about half an inch to an inch.

Is it okay to call the pediatrician for small things?

Yes. Pediatric offices and nurse lines expect calls from new parents. If you're unsure whether something is normal, call. It's what they're there for.

Sources

  1. Fever and Your Baby, American Academy of Pediatrics (HealthyChildren.org)
  2. When to Call the Pediatrician: Fever, AAP (HealthyChildren.org)
  3. Jaundice in Newborns: Parent FAQs, AAP (HealthyChildren.org)
  4. When to get urgent medical help for babies and children under 5, NHS

We link to the original source for every medical and safety claim. Guidance changes; if a source has been updated since our last review, the source wins. How we research.