A new digestive system

Your baby's digestive system is brand new and still learning the ropes. It works differently from yours, and that explains a lot of the grumbling.

The muscle at the top of the stomach, the lower esophageal sphincter, is still loose, which is why spit-up comes up so easily. The stomach itself is small and makes fewer digestive juices, so breaking milk down is real work. And the intestines are shorter and move things along fast, which means gas and some interesting diapers.

The system is new rather than broken, and most of it settles as it matures.

Doulores

A newborn stomach grows fast in the first few days, learning to relax and take more. I'd read small, frequent feeds as the size of the tank rather than anything going wrong.

Spit-up, and what helps

Most spit-up doesn't hurt at all and is only a problem for the laundry. But when it touches the lining of the esophagus it burns, the way heartburn does in an adult, and that wakes a baby.

The happy spitter brings milk up easily, often with a burp, then carries on. Growing well, sleeping fine. That's normal reflux and it's a laundry problem.

The uncomfortable refluxer brings it up with crying, arching, or turning away from the next feed. It wakes them, and it makes settling hard. That one looks like GERD, and it's worth talking to your doctor about.

Gravity is on your side either way. Holding your baby upright after a feed is the most useful thing you can do about reflux, and most babies with straightforward reflux get better with small things like this. Upright keeps milk down and away from that loose valve, lets the stomach work without everything sloshing about, and lets trapped air come up as a burp. Twenty to thirty minutes held or in a carrier, before they go down flat, is long enough for the stomach to start emptying.

Even with reflux, back sleeping is safest.

Doulores

Pain is the thing that disrupts sleep, not the mess. If your baby is happy and gaining, I'd treat reflux as laundry rather than a medical problem. Painful symptoms are a different conversation.

Gas

Gas is air stuck where it shouldn't be. Usually it's air your baby swallowed, caught somewhere on the way out, and the pressure is enough to wake them. Gas pain tends to come during or just after a feed, and again in the lightest stage of sleep, which is why it wakes them when it does.

Some of it comes from digesting: a new gut working on milk sugars makes gas on its own, and it builds through the day. Gulping from a bottle, or through a strong letdown, takes air down with the milk. And crying takes in air, which makes gas, which makes more crying.

Burping gets it out. Over your shoulder, patting or rubbing their back. Sitting on your lap with their chin supported, leaning forward a little. Or face down across your lap, with gentle pressure on their back. Mid-feed and after, and don't force it if nothing's coming.

Heading it off is the other half. Paced bottle feeding slows the flow so less air goes down. Get the latch checked if you're breastfeeding. Anti-colic bottles are made to let less air through. And tummy time while they're awake builds the core and helps things move.

Doulores

Burping helps many babies and not all of them need it. Some breastfed babies swallow very little air, so I would not treat a missed burp as a mistake.

How much, and how fast

Sometimes it isn't the milk, it's how fast it arrives. A forceful letdown can overwhelm a baby, so they gulp, take air down with it, and end up fussy or spitting up more.

You'd see them pull off, cough or splutter once the milk starts coming. Milk sprays when you express, or when they unlatch. They're gassy or fussy, or they arch their back during and after feeds. And weight gain is fine, while the feeds themselves feel chaotic and they seem uncomfortable. It's usually very fixable. If none of this eases their discomfort, or you are unsure about latch or positioning, a lactation consultant can watch a whole feed and see what no article can, and it's worth asking sooner rather than later.

On volume, rather than aiming at a number, follow their cues: feed when they're hungry, stop when they're full. That teaches them to read their own body. What you're watching is the cues, the wet diapers, and steady weight gain.

Signs of too much
  • Frequent, forceful spit-up
  • Gassy, bloated, uncomfortable
  • Weight climbing faster than expected
  • Turning away from feeds, then taking them anyway
Signs of not enough
  • Fewer than 6 wet diapers daily after day 5
  • Poor weight gain, or weight loss
  • Hunger cues that never let up, and fussing
  • Dark yellow, strong-smelling urine
Doulores

Moving more calories into the daytime sometimes helps: they take in more while alert and digest it better, which can reduce night hunger. I'd check any weight or feeding change with your doctor rather than adjust it alone.

Hungry, or uncomfortable?

Knowing how digesting lines up with sleeping helps you tell a hungry waking from an uncomfortable one.

Breast milk clears the stomach in an hour and a half to two hours, and formula in three to four, which is why breastfed babies feed more often. Discomfort peaks 30 to 90 minutes after a feed, as things get moving. And gas is usually worse in the evening, after a day of it building.

So the 45-minute waking is often gas. A waking at three or four hours may be hunger, if the last feed has cleared. And early morning waking is sometimes an empty stomach and sometimes gas.

Doulores

That 45-minute mark often lines up with digestion moving along. Gentle tummy massage or bicycle legs before bed may head it off, and I'd try that before changing anything larger.

When to get it checked

Most of this is ordinary and passes. Knowing the exceptions is what lets you stop watching for them.

Ordinary and passing
  • Growth spurts: feeding more often for two or three days
  • New skills: more spit-up once they start moving differently
  • Vaccination days: digestion can be off for a bit
  • Minor illness: appetite and digestion shift, then come back
Call for help now
  • Call emergency services if your baby turns blue or dusky around the lips or face, or if their breathing is labored, fast, or stops.
  • Call your doctor the same day if breathing sounds wheezy or rattly with spit-up, or if feeds are repeatedly interrupted by coughing or choking.

The best preparation for this is an infant first-aid course. Keep your out-of-hours number somewhere you can find it fast.

When to talk to your doctor
  • Weight concerns: Poor gain or excessive gain
  • Blood in spit-up or stool: Always requires evaluation
  • Extreme discomfort: Inconsolable crying for hours, arching back and grimacing after every feed/still looking like in pain after burping
  • Feeding refusal: Lasting more than 2 feeds
Safety
  • Back to sleep: Even with reflux, back sleeping is safest
  • No positional devices: Wedges, positioners not recommended
  • Medication only if prescribed: Never give adult reflux medications
Doulores

Cluster feeding is a stretch of very frequent nursing, and it is doing a job: it drives milk production up when supply needs to catch up with them. I'd expect it rather than treat it as a problem.

If you are having thoughts of harming yourself or your baby, this is the moment to get help now, not at the next appointment. Call emergency services, or reach out to a local crisis line. If someone is with you, tell them, and ask them to stay.

Frightening thoughts that arrive uninvited and horrify you are far more common after a baby than most people know, and having them does not mean you will act on them or that anyone will take your baby away. They are still worth telling someone today. If you feel you might act, or you cannot be sure, treat that as an emergency and call.

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