09/08/2026
Does your baby back arch & strain to poo?
Screaming, straining, red in the face — and then a perfectly soft nappy?
That's probably not constipation. It's called infant dyschezia, and it's not a poo problem - it's a coordination problem.
It's like squeezing a tube of toothpaste! To get a poo out, your baby has to do three things at the same time:
- Hold on to the tube (activate their core),
- Squeeze from the top (contract their diaphragm),
- Take the lid off (relax their pelvic floor).
Newborns are brilliant at the squeezing, it's usually the relaxing bit they haven't worked out yet, so they push and push against a closed cap, until eventually it opens and out comes a soft poo.
It's a skill, not a problem.
To get into the right shape for pooing, a baby needs to curl — knees up, bottom tucked, chin down - it's like a squat position. Some babies are much happier in the opposite shape. They live in extension: back-arching, pushing back, straightening out.
Does this sound like your baby?
→ Arches backwards when upset, or when you lay them down
→ Straightens their legs rather than bringing knees up
→ Fights being curled - resists the tucked-up cuddle
→ Arches out of the car seat or bouncer
Lying on their back is often not the best position. It's the easiest position to straighten out in, and the hardest to curl up in.
Try side-lying instead.
Roll them onto their side and that barrier disappears. The arching has nowhere to go, and everything else falls into place on its own. Hips bend. Knees drift up. Chin tucks.
That's the whole curled-up shape they need for pooing, and they find it without you holding them there. A few minutes at a time when they're calm and awake - always on their back for sleep.
Other things such as nervous system dysregulation or asymmetrical movements can contribute but get started with the side-lying and see how it goes. If you need a bit more help, you know where we are x