“Potty Regression” and “Potty Refusal”: What’s Really Behind Toileting Accidents

By Steve Hodges, M.D.

Editor's note: This post has been updated to reflect Dr. Hodges' current clinical guidance.

When young children start having accidents months—or even years—after successful potty training, parents are often handed tidy explanations: “potty regression,” “potty refusal,” or the claim that the child is “not fully potty trained” or hasn’t been “nighttime potty trained.”

These labels suggest something psychological or behavioral has gone off the rails or that more “training” is needed. In reality, they send parents on wild goose chases, while the real culprit—chronic constipation—goes untreated.

And the consequences go beyond parental confusion. Misleading terms like these even fuel misguided legislation, such as recent bills in Kansas and Utah aimed at requiring kindergartners to be “potty trained,” as if accidents were a training failure.

In this post, I’ll explain why terms like “potty regression” and “not fully potty trained” are misleading, how constipation stealthily drives toileting accidents, and what it actually takes to reverse the problem before accidents—and the fallout they cause—escalate.

“Potty Regression”

The other day, a mom emailed me about her 33-month-old daughter, who had started having pee accidents three months after successful potty training.

“I can’t tell if this is just a bit of a regression,” she wrote. “There haven’t been any life stressors or changes, so I am stumped.”

I wasn’t stumped. This wasn’t potty regression. It was the progression of chronic constipation and had nothing to do with the girl's stress level.

Here’s what's going on in situations like this:. The child, for any number of reasons, develops a habit of delaying bowel movements, allowing stool to accumulate in the rectum. As the rectum enlarges, it presses on nearby bladder nerves, triggering sudden, forceful bladder contractions. The bladder essentially “hiccups” and empties without warning.

Once wetting begins, it’s often labeled a regression, implying that a child has somehow lost previously mastered skills. The explanation typically shifts to emotional stress—a new sibling, a move, a change in routine—even though there’s no credible evidence that stress causes toileting accidents.

This idea is widely reinforced by experts. A Washington Post parenting columnist, for example, advises parents to “get ready for regression” during stressful periods, assuring readers this is “not abnormal” and “not a problem.”

In reality, persistent accidents are abnormal, and they are a problem. Not a psychological one, but a medical one. And while the problem is very fixable, it requires treatment, not assurance that it will resolve on its own.

Parents are particularly surprised when accidents begin not months but years after toilet training, around age 5 or 6. But this, too, is predictable. School introduces longer days, bathrooms that are farther away, and subtle pressure (or even rewards) from teachers to “hold it" until the bell rings. Withholding increases, constipation worsens, and eventually the rectal stool burden reaches a tipping point—and accidents start. Holding pee exacerbates the problem by further aggravating the bladder.

Recognizing this pattern early matters. Once constipation has progressed to accidents, reversing it is rarely as simple as parents are led to believe.

READ: Kindergartners in Diapers: What’s Really Going On and How Teachers Can Help 

“Potty Refusal”

The term “potty refusal” is commonly used to describe toddlers who “won’t” toilet train and older children who have been toilet trained but nonetheless have poop accidents or will only poop in a pull-up. In all these cases, the implication is the same: the child is being willful or stubborn.

I hear this often from anguished parents: “My child REFUSES to poop on the toilet,” or “My child is strong-willed and has picked the potty as her primary battle.” 

Parenting experts—and even physicians—echo this language, sometimes elevating it to diagnoses like “stool toileting refusal” or “toileting refusal syndrome,” terms I’ve encountered in medical journals.

But in these scenarios, "refusal" is the wrong word.

When a toddler resists toilet training, it’s because the child isn’t mature enough to train or is already constipated when training begins. When an older child avoids pooping on the toilet, it’s because constipation has made pooping hurt—trying to pass a hard, dry mass of stool is painful—or has stretched the rectum so much that the child no longer feels a strong urge to go.

Poop accidents happen when the rectum becomes so full and stretched that it loses tone, and stool simply leaks out.

That isn’t defiance. It’s physiology.

We don’t say a 2-year-old is “refusing” to ride a bike; we recognize the child isn’t ready. We don’t say a 7-year-old is “refusing” to read; we identify a learning issue and address it. Toilet use should be no different.

Instead, parents are often advised to “motivate” a child to poop on the toilet with rewards—M&Ms, stickers, or screen time—or to take the opposite approach and back off completely. Parenting coaches and therapists commonly reassure families: Don’t push. Don’t mention the toilet. This will pass.

Neither approach solves the problem. A clogged rectum doesn’t resolve itself any more than a clogged drain pipe does. Left untreated, constipation commonly progresses to encopresis (chronic poop accidents) and enuresis (bedwetting or daytime wetting)—conditions I routinely see in older children whose difficulties were evident in preschool but went unaddressed.

Ironically, studies linking “potty refusal” to later toilet training are often cited as evidence of behavioral resistance—when they actually point to the same underlying problem: constipation.

For example, a study published in Pediatrics followed nearly 400 children and found that over 24% developed “stool toileting refusal," including 50% of children who trained between ages 3 1/2 and 4. These children were described as having hard bowel movements and pain when pooping—and 93% showed signs of constipation before the onset of so-called refusal.

In other words, these children began toilet training with a condition that makes toilet training profoundly difficult, if not impossible.

Labeling them “refusers” misses the point. When constipation is treated appropriately, the “refusal” disappears.

READ: “Nagging” Your Child to Use the Toilet: Are Potty Sits Useful? 

"Not Fully Potty Trained”

Parents often tell me their child is “not fully potty trained” or that the child is “pee trained but not poop trained.” When I ask what they mean, the answer is either: 1.) the child is having poop accidents, or 2.) the child pees on the toilet but resists pooping there. Both scenarios are red flags for chronic constipation—and neither has anything to do with “training.”

Telling a child to “listen to your body” or “go when you feel the urge” doesn’t help when the body isn’t sending a clear signal. Yet accidents are often treated as evidence that a child needs more instruction. Preschools commonly send children home to “work more on potty training,” and I’ve had patients suspended from school because they were deemed “not fully potty trained.”

Potty training, however, isn’t like driver’s training. Sure, instruction matters initially—how to get on the toilet, when to try, how to wipe. But children who are developmentally ready and not constipated don’t need months of coaching and practice. Using the toilet comes quickly and naturally.

If a child is still having accidents three months later, the problem isn’t a lack of training—it’s that something is interfering with normal bowel and bladder function.

Address that problem, and the notion of being “not fully potty trained” quietly disappears.

“Nighttime Potty Training”

Parents often ask me when they should begin “nighttime potty training" or use this language to describe children who are dry during the day but need pull-ups at night.

This idea that overnight dryness can be taught is heavily promoted by potty-training coaches and product manufacturers.

Potty-training books frame nighttime dryness as a final hurdle that requires parental effort and resolve. One author writes that “becoming dry at night requires a devoted effort on your part. Don’t shirk your parental responsibilities!"

Some products suggest that diapers themselves create dependence, and that feeling wet overnight will motivate a child to stay dry. One manufacturer bills its absorbent pajamas as the "alternative for nighttime potty training" and describes pull-ups as a "crutch that only delay a child's ability to potty train at night.”

That’s not how nighttime dryness works.

READ Nighttime Potty Training is Not a Thing

Children become dry at night naturally—no training required. If a child isn’t dry by around age 4, the reason is likely chronic constipation. (An abdominal X-ray can confirm this.) A rectum enlarged by a poop pile-up triggers the bladder to hiccup and empty while the child is sleeping.

Withholding diapers doesn’t fix the problem. It just makes children uncomfortable while the underlying issue goes untreated.

I’m generally not inclined to police language. But when it comes to toileting, terms like "potty regression," "potty refusal," "not fully potty trained," and “nighttime potty training” do real harm. They reinforce the false idea that accidents reflect insufficient effort—by the child or the parent—rather than an untreated medical condition.

Different labels, same root problem: untreated constipation.

So, how do you treat the constipation driving these accidents?

Once toileting problems have progressed to accidents (or bedwetting persists in children 4 and older), the usual advice—more fiber, “potty sits,” Miralax—won’t resolve the underlying problem.

Reversing chronic constipation requires a three-step process, carried out in sequence. The Modified O’Regan Protocol (M.O.P.), the approach I use in my clinic, is designed around these steps:

Step 1: Empty the rectum. This takes longer than most families expect. M.O.P. uses a structured combination of enemas and laxatives to clear the accumulated stool.

Step 2: Keep the rectum empty long enough to heal. It takes a good 3 months for the rectum, once emptied, to shrink back to normal size, regain tone and sensation, and stop irritating the bladder nerves.

Step 3: Retrain the child to act on the urge to poop. Once children can actually feel the urge to poop again, they need help responding to it instead of automatically delaying.

This process takes time, consistency, and follow-through—and it’s far more involved than most parents (and many clinicians) realize.

If you want a step-by-step guide to implementing this approach, The M.O.P. Anthology explains what to do, why it works, and what to expect along the way.

Because resolving accidents isn’t about more training, better motivation, or waiting it out. It’s about treating the right problem—thoroughly enough that the symptoms finally stop.