Expert Tips: Causes of Baby Constipation & How to Relieve It

Posted on 8-04-218-06-21 by Dr. Harvey Karp

woman bicycling baby's legs to help relieve constipation — Photo by Prostock-studio/Shutterstock

Grandma may have warned you how important it was to “stay regular”—and that’s good advice for babies, too!

Your baby may be constipated if they have hard or pellet-like poops and grunt/cry when it’s time to poop. Typically, babies poop two to three times per day, or even four to five times per day for some infants. If your baby has not pooped in two to three days, then it’s a good idea to call the doctor.

Breastfed babies almost never get constipated. They may grunt and strain…or even skip a few days between poops—or even a week!—during the first couple of months, but even then, the bowel movements stay loose to pasty. Bottle-fed babies, however, sometimes struggle to pass hard little pieces of poo.

Fortunately, a couple of commonsense ideas can usually correct the problem.

What causes baby constipation?

Diet is the top cause of constipation in little ones. The intestines of some babies can be sensitive to certain brands of formula (or even particular type of preparation—powdered or concentrate). Or your baby may be battling a dairy or soy allergy (a doctor can help determine if this is the case).

A change of diet can also slow the flow of a baby’s BMs. Sometimes when babies are given the greenlight for baby food, they can struggle with constipation. Many first-time foods end up being very starchy and binding (think rice and banana). In fact, those are foods doctors recommend to firm things up when infants have diarrhea.

If your baby isn’t getting enough water, this can lead to hard poo, too. It’s super easy to check for this problem: The inside of the mouth will get a bit dry and sticky; your baby will pee fewer than six times a day; the urine will become much yellower and a bit smelly.

Finally, if you’re baby’s taking iron supplements, you might notice that your little one’s poops have become hard black-green colored pellets.

What to do if your baby is constipated:

Open the door. Babies trying to poop often have a hard time squeezing the stomach muscles and relaxing the rectum…at the same exact time. They accidentally tighten the anus as they tighten the stomach, and consequently, they strain to get the poop “out the door!” To relax your baby’s anus, bicycle their legs and gently press their knees down to their stomach a few times. Another helpful tip is to insert a Vaseline-greased thermometer or cotton swab— just 1 inch—into the anus. That usually makes babies bear down to push the object out…often pushing the poop out at the same time.
Change formula. Talk to your pediatrician for guidance on this, but trying a new formula sometimes softens stool. Also, some infants have an easier time pooing when they drink ready-made formula versus powder-based (or vice versa!).
Dilute the formula mix slightly. Your baby’s poops may improve if you add ½-1 ounce of extra water to one to two bottles per day (only do this with your doctor’s approval). Note: Never dilute the formula more than that.
Change up solid foods. White foods (like rice, grains, dairy, bananas) bind a baby up. But certain foods can help get pooping back on track. Some doctors recommend adding a tablespoon of organic adult prune juice or ½-1 ounce of fresh aloe juice once or twice a day.

Note: Never give honey or corn syrup as a laxative before the 1^st birthday. They can cause infant botulism, a frightening cause of infant paralysis.

When to be concerned about baby constipation:

After the first couple of weeks, babies usually settle into a pretty good pooping routine. For bottle-fed babies, that schedule is one to two times a day. Breastfed babies may skip a day or so in between bowel movements. In fact, by 1 month of age, they sometimes go a week (or, even two) without having a stool!

Call your little one’s doctor if more than three days pass without a poop or if the poops are too firm. Ring them up even sooner if your baby has a weak cry, weak suck, or is acting sick.

Dr. Harvey Karp is a world-renowned pediatrician and child development expert. His celebrated Happiest Baby/Happiest Toddler books and videos have guided millions of parents and are translated into 30 languages. In 2016, Dr. Karp debuted SNOO Smart Sleeper, a new class of responsive infant bed designed to add 1-2 hours to a baby’s sleep, quickly soothe crying and to improve safety by preventing dangerous rolling. SNOO won the National Sleep Foundation Innovation of the Year award as well as 20 other top national and international honors. Medical studies are underway to evaluate SNOO’s potential to reduce postpartum depression, infant sleep death and to improve the care of infants withdrawing from opiates. Dr. Karp is an Assistant Professor of Pediatrics at the USC School of Medicine and a fellow of the AAP. He is an advocate for children’s environmental health and a board member of EWG, whose mission is to protect our nation’s public health and the environment.