Q&A: What's Wrong With My Baby's Poop?

What could make my baby's poop mucousy and stinky?
ByJeanne Cygnus, IBCLC, RLC
Lactation Specialist
Updated
Feb 2017
Hero Image
Photo: Getty Images

When a baby is exclusively breastfed, his poop is generally very mild smelling and the consistency may be either liquid or cottage cheese-like. Adding in anything else to his diet, such as formula or other supplements, can cause a dramatic change in odor and appearance of poop.

If your baby is getting nothing but breast milk and suddenly develops a lot of mucus or blood in his stool, and the odor is foul, then it is important to have him checked by his doctor. It is possible that he is reacting to a protein in mom’s diet — such as cow’s milk — causing his gut to become raw and irritated. It is also possible that he has a bacterial or viral infection that needs further treatment. If he is running a fever or not eating well, then it is important for him to be checked right away. If he is otherwise content, but you’re noticing a lot of mucus in his stools, then you may want to keep track of what you’re eating, and see if the mucus subsides with a change in your diet. If it does not resolve, or it gets worse, then a trip to your doctor is warranted.

Related Video

Diarrhea in Babies

Paul Horowitz, MD
Pediatrician

DYPER Launches First-Ever National Diaper Composting Service

Nehal Aggarwal
Associate Editor
Published
02/19/2020

Q&A: What's Wrong With My Baby's Poop?

Jeanne Cygnus, IBCLC, RLC
Lactation Specialist

What Should Formula Poop Look Like?

-- Sabrina Braham, MD, pediatrician in Menlo Park, California and adjunct clinical faculty member at Stanford University
Pediatrician

Newborn Poop?

The Bump Editors

Bloody Stools in Babies

Paul Horowitz, MD
Pediatrician

Green Toddler Poop?

Michael Lee, MD, assistant professor of pediatrics at UT Southwestern Medical Center and pediatrician at Children’s Medical Center Dallas
Pediatrician

Q&A: Baby's Pooping Eight Times a Day. Is This Normal?

Deborah Davis, MD, pediatrician
Pediatrician

Mom’s Tale of Cleaning Poop Off a Slide Has the Internet Cracking Up

Laurie Ulster
Contributing Writer
Published
10/03/2019

Q&A: What's Normal Baby Poop?

Dr. Leigh Serra
Pediatrician

Q&A: How Much Pooping Is Normal?

Jeanne Cygnus, IBCLC, RLC
Lactation Specialist

How Will I Know if Baby Has Diarrhea?

Jack Newman, MD, FRCPC
Pediatrician

How Can I Fix Baby's Constipation?

Excerpted from You Raising Your Child by Mehmet C. Oz, MD, and Michael F. Roizen, MD