16 August 2026 · Veronica Chi
Business & Product Director · Mum of two
Why Blowouts Happen — and How to Stop Them
There is a specific sound. Then a pause, while everyone in the room performs the same silent calculation about whose turn it is. The up-the-back blowout is a rite of passage, usually arriving on the day you have dressed the baby in something you actually like.
Blowouts are not random, and they are not a sign that you have bought the wrong diapers. They are mechanics, and mechanics can be adjusted.
Why it goes up the back
Newborn stool is loose and arrives with force. A diaper is designed to absorb liquid downward and outward through the core, but very loose stool does not absorb — it flows, and it flows toward the lowest-resistance gap. In a baby lying on their back, that gap is at the waistband behind them.
Three things make it worse: a waistband gap at the back, a diaper too small in the rise so the back sits low, and a baby who has just been fed and is now horizontal, which describes most newborns most of the time.
The fit fixes
- Pull the back panel higher than the front. This is the single most effective change and costs nothing.
- Run a finger around the entire waistband after fastening. If you can slide a finger flat into a gap at the back, so can everything else.
- Pull the leg cuffs outward. Tucked cuffs cause leg leaks, and a leg leak often becomes a back leak once the baby is picked up.
- Size up if the tabs are fastening at the outer edge or the rise no longer reaches the belly button. A diaper too small in the rise cannot seal at the back regardless of technique.
- Check the fit again after a feed. Babies change shape considerably between empty and full, and the fit you set an hour ago is not the fit you have now.
Is a blowout ever a health signal?
Occasionally. Frequent, unusually watery stools — particularly with a fever, blood or mucus, an unsettled baby, or fewer wet nappies than usual — are worth a doctor's opinion rather than a change of diaper brand. Dehydration moves quickly in small babies and in this climate.
Routine newborn blowouts, in a baby who is feeding and gaining well, are simply what the first months look like. Breastfed newborn stool is loose by design.
Getting the bodysuit off
Baby bodysuits have envelope folds at the shoulders. They are not a manufacturing quirk and they are not for stacking sizes — they exist so that a soiled bodysuit can be pulled DOWN over the shoulders and off past the feet, rather than up over the head.
Most parents discover this in month four, having spent the preceding sixteen weeks pulling soiled clothing over their baby's face. Consider this your early notification.
The out-of-the-house kit
A blowout at home is a laundry event. A blowout at Takashimaya is a logistics event. The difference is entirely in what is in the bag.
- A full change of clothes, not just a spare bodysuit. Assume total loss.
- A wet bag or a sealable plastic bag. Nursing rooms here are excellent, but they are not laundries.
- More wipes or cloths than seems reasonable. Double whatever number you first thought of.
- A muslin cloth, which will serve as a changing mat, a screen, a towel, and eventually as the thing you wrap the whole situation in.
- A spare top for yourself, once you have learned this lesson the hard way exactly once.
Questions parents ask
Why do diaper blowouts go up the back?
Very loose newborn stool flows rather than absorbing, and moves toward the lowest-resistance gap. In a baby lying on their back that gap is the rear waistband. Pulling the back panel higher than the front is the single most effective fix.
How do I stop diaper blowouts?
Pull the back panel higher than the front, run a finger around the whole waistband to check for gaps, pull the leg cuffs outward rather than tucking them in, and size up if the tabs fasten at the outer edge or the rise no longer reaches the belly button.
Are frequent blowouts a sign of a problem?
Usually not — loose stool is normal in breastfed newborns. See a doctor if stools are unusually watery and frequent alongside fever, blood or mucus, an unsettled baby, or fewer wet nappies, since dehydration moves quickly in small babies.
How do you get a soiled bodysuit off a baby?
Use the envelope folds at the shoulders — they exist so the bodysuit can be pulled down over the shoulders and off past the feet, rather than up over the baby's head and face.
What should I pack for a blowout when out of the house?
A full change of clothes rather than just a bodysuit, a sealable wet bag, roughly double the wipes you think you need, a muslin cloth that can act as mat, screen and towel, and a spare top for yourself.