The first three months with a baby contain a lot of unexplained crying, and most of it is rooted somewhere in the gut. Wind, reflux, colic, evening fussiness — different labels for an immature digestive system finding its feet. Knowing what's normal, what helps, and what isn't normal saves a lot of late-night spiralling. For a comprehensive overview, see our complete guide to child health.
Why So Much Tummy Trouble in the First Months
A newborn's gut is a working draft. The valve at the top of the stomach (lower oesophageal sphincter) doesn't close fully, which is why milk slides back up so easily. The gut bacteria are still arriving and arguing about who lives where. The muscle coordination that moves milk along is still being learned. And babies swallow a remarkable amount of air — between feeds, during crying, while learning to breathe through a small new nose.
Add it up and some level of digestive discomfort in the first 12–16 weeks is essentially built into the design. Most parents find symptoms peak at around six weeks and ease meaningfully by three or four months. That isn't false reassurance — it's the timeline the gut keeps for itself.
Wind
Trapped wind is the everyday version. Signs: pulling the legs up, wriggling against you, a tight belly, sudden cries between feeds, and eventually relief that announces itself loudly.
What helps:
- Wind during the feed, not just after. For bottle-fed babies, halfway through is a natural pause. Breastfed babies often wind themselves between sides; if not, the same halfway pause works.
- Feed semi-upright rather than flat — even a 30–45° tilt cuts down on swallowed air.
- Bicycle legs and a clockwise tummy rub between feeds (clockwise follows the colon's direction). Not straight after a feed — wait 15–20 minutes or you'll bring the milk back.
- Check the latch on the breast — clicking sounds, dimpled cheeks, or pain are signs of a shallow latch that lets in air.
- Match the bottle teat to your baby. Slow flow for newborns; if you see them spluttering, gulping, or milk leaking from the corners, the flow is too fast.
Anti-colic bottles (with vents or angled necks) help some babies measurably. Simethicone (Infacol) and gripe water have weak evidence — trials don't show much, but parents often report improvement, and there's no harm. The ritual of giving them may matter as much as the drug.
Colic
Colic is the diagnostic label for crying that's hard to explain — formally, more than three hours a day, more than three days a week, in a baby under three months, in a baby who's otherwise well and gaining weight. It usually shows up at two to three weeks, peaks around six weeks, and is gone by three to four months.
The "witching hour" between roughly 5pm and 9pm is the classic colic pattern. Nobody knows exactly why. Best guesses combine an immature gut, a still-forming microbiome, a baby's nervous system getting overwhelmed at the end of the day, and parents who are themselves running on empty by that time.
Things that help, in rough order of how reliably:
- Carrying with motion. Slings, walking, slow rocking, the legendary drive around the block. Continuous rhythm, not bouncing on the spot.
- Skin-to-skin on a parent's chest. Familiar smell, familiar heartbeat.
- White noise. A vacuum, a hairdryer at distance, a white-noise app. The womb was loud — silence isn't soothing.
- Swaddling for younger babies (until they show signs of rolling, then stop).
- One feeding tweak at a time. Latch, teat flow, semi-upright posture, smaller more frequent feeds.
- A two-week dairy-free trial in the mother's diet for breastfed babies if colic is genuinely severe and other things haven't helped — supported by NICE for suspected cow's milk protein allergy. If it doesn't help in two weeks, dairy goes back in.
What doesn't help: trying every remedy at once for two days each. Pick one or two changes and give them at least three to five days.
The other thing worth saying: severe, sustained colic is genuinely hard on parents. Sleep deprivation plus relentless crying is a real risk for postnatal depression and for shaken baby injury. If you ever feel close to losing your patience, put the baby down somewhere safe in their cot and walk into another room for five minutes. That isn't failure — it's the recommended advice.
Reflux
Most babies bring some milk back up after feeds. The stomach is small, the valve at the top is loose, and they spend most of the day lying down. This is gastro-oesophageal reflux (GOR), and on its own it doesn't need treatment. The "happy spitter" — bringing up half a feed, perfectly content, weight tracking nicely — needs a muslin, not a medicine.
What it isn't is gastro-oesophageal reflux disease (GORD), which is reflux that's actually causing trouble: pain (back-arching during or after feeds, screaming), refusing feeds, weight faltering, recurrent chest infections, or apparent breathing pauses. That's different and needs reviewing.
For everyday spitty reflux:
- Hold them upright for 20–30 minutes after feeds. The single most useful change.
- Smaller, more frequent feeds — easier on a small stomach.
- Wind well during the feed so trapped air doesn't push milk back up after.
- Anti-reflux (AR) formula thickens in the stomach and reduces visible vomits in formula-fed babies — useful if reflux is heavy. Don't use AR formula and a thickener at the same time.
- Avoid bouncing or vigorous play straight after a feed.
For breastfed babies, positioning changes during feeds, and (where suspicion is high) a trial of cow's milk protein elimination in the mother's diet are the next steps. Don't put babies to sleep upright or propped — flat-on-back stays the safe-sleep rule even with reflux.
If symptoms point at GORD — pain, poor gain, breathing problems — that's GP territory. Treatment ladders from feed thickeners to alginates (Gaviscon Infant) to acid-suppressing medication (omeprazole, ranitidine has been withdrawn in most places). These are prescribed when there's a real reason, not for ordinary spitting.
When to Get It Checked
Same-day review for:
- Not gaining weight, or losing weight
- Inconsolable crying for more than three hours despite the usual soothing
- Forceful (projectile) vomiting — particularly in a baby 2–8 weeks old, where pyloric stenosis sits in the differential
- Vomit that's green or yellow (bile), or contains blood
- Blood in the nappy
- Significant pain after every feed, arching, refusing feeds
- Any fever in a baby under three months — separate rule, no exceptions
Most early tummy trouble is a phase the gut grows out of. The job in the first few months is to reduce the discomfort where you can, ride out what you can't, and stay alert to the small set of patterns that aren't normal. You know your baby's baseline better than anyone — if something feels beyond ordinary fussiness, that instinct is worth following.
Key Takeaways
Most early tummy trouble — gas, colic, reflux — comes from a system that hasn't finished assembling yet. It peaks around six weeks and is usually gone by three to four months. Winding well, semi-upright feeding, smaller more frequent feeds, and 20 minutes upright after a feed do most of the work. Anti-colic bottles, simethicone, and the once-recommended dairy-free trial in breastfeeding mothers help some babies; expensive remedies mostly help the parents who buy them. Same-day review for poor weight gain, projectile or green/yellow vomit, blood in stool, inconsolable crying past three hours, or any fever in a baby under three months.
