Reflux and spit-up in babies

Babies bringing up milk — “posseting”, spit-up, or reflux — is one of the most common things new parents ask about. Most of the time it’s completely normal and harmless (if messy), and your baby grows out of it. Sometimes it needs a bit more attention. Here’s how to tell the difference and what helps.

What reflux is. Reflux is when milk comes back up from the stomach, because the muscle at the top of a baby’s stomach is still immature and doesn’t hold everything down. Most babies have some reflux, especially in the early months, and it usually improves as they get older (often much better by around 6–12 months as they sit up and start solids).

“Happy spitters”. The key reassurance: a baby who spits up but is otherwise well, feeding, and gaining weight — a “happy spitter” — is doing fine, even if the volume of laundry suggests otherwise. Posseting a bit of milk is a laundry problem, not a medical one. It looks like more than it is.

Simple things that help. For ordinary reflux:

• Keep feeds calmer and burp your baby during and after feeds
• Hold your baby upright for 20–30 minutes after feeding
• Try smaller, more frequent feeds rather than large ones
• Check the latch (breastfeeding) or teat flow (bottle) so they swallow less air
• Avoid tight nappies or waistbands pressing on the tummy after a feed

Safe sleep still applies. Despite reflux, always put your baby to sleep on their back on a firm, flat surface — do not prop the cot up or use wedges or pillows, which aren’t recommended and can be unsafe. Back sleeping is safest even for refluxy babies; babies protect their airway when on their back. If you’re worried about reflux and sleep, talk to your child health nurse rather than tilting the cot.

When it might be more than normal reflux. Sometimes reflux causes problems (sometimes called GORD) or there’s another cause. See your GP or child health nurse if your baby: isn’t gaining weight or is feeding poorly/refusing feeds; is very unsettled, arching or in pain with feeds; has frequent forceful vomiting; or the reflux is really affecting them. Don’t start reflux medications or change formula on your own — these are only sometimes needed and should be guided by a doctor.

Red flags — get checked promptly. Seek medical advice urgently if your baby has green or yellow vomit, projectile (forceful) vomiting, blood in the vomit or poo, a swollen or hard tummy, a fever, is very sleepy or hard to rouse, is dehydrated (few wet nappies), or vomiting alongside not feeding. These can signal something other than simple reflux and need prompt assessment.

Looking after yourself. Constant spit-up, extra laundry and an unsettled baby is wearing. Keep muslin cloths everywhere, dress for the splatter, and remember it’s a phase. If your baby is a genuinely unsettled, painful feeder and you’re exhausted, lean on your child health nurse — and services like Tresillian or Karitane — for support.

“Silent” reflux. Sometimes milk comes up and is swallowed again rather than spat out, so you don’t see much on the outside — sometimes called silent reflux. A baby who swallows it back may still be a bit unsettled around feeds, but the same reassurance applies: if they’re well, feeding and gaining weight, it’s usually nothing to worry about and improves with age. It’s only worth acting on if your baby is genuinely distressed, not feeding well, or not thriving — in which case, see your GP or child health nurse rather than assuming and treating it yourself.

Most baby reflux is normal, harmless and outgrown — a well, growing “happy spitter” just needs patience, muslin cloths, and the simple upright-and-smaller-feeds measures. Keep to safe back sleeping, watch for the red flags, and see your GP if your baby is unsettled, not gaining, or the vomiting looks different. When in doubt, get them checked.