If your baby won’t open their mouth wide to latch, it can feel terrifying.

Feeding is supposed to be simple. But when your newborn isn’t opening their mouth wide enough to latch — especially in those early days after birth — it can turn every feed into constant worry.

If you’re struggling because your baby won’t open their mouth, you’re worried about whether they’re getting enough milk, and you’re wondering if feeding will always feel like this — this post is for you.

I’ll walk you through why this happens, when to worry (and when not to), and how to make feeding feel better.

Baby Won't Open Mouth to Latch - When to Worry

Newborn babies have an incredible ability to sleep deeply. While this is great for photos, it can make feeding every 2–3 hours feel stressful — especially in the beginning when you’re still figuring it out together.

Let’s break down what’s normal newborn behavior versus when a baby not opening their mouth wide enough to latch can be a sign to reach out for help.

Normal Newborn Behavior

Skipping one feed in that 2–3 hour window is usually okay. That guideline exists to make sure babies get enough total calories in a day.

Here’s the truth: one feed doesn’t make or break things.

It’s also very normal for a newborn to take a longer stretch of sleep — and nearly impossible to wake them during it. What matters is the overall pattern. Signs things are on track include:

• Feeds at shorter intervals during the rest of the day.
• Stays awake to feed for 15–20 minutes without constant stimulation.
• Plenty of swallows during feeds.
• 4+ dirty diapers daily at 4 days old and beyond.
  
  

When Not Opening Is an Emergency

If your baby has been hard to wake for more than two feeds in a row — and it’s getting harder each time — it’s time to call your provider.

Other red flags to watch for include:

• Not enough wet or dirty diapers for their age.
• Too weak to feed or stops after only a few seconds.
• Refusing to open or latch at all across multiple feeds.
• Signs of dehydration (dry mouth, sunken fontanelle, unusual lethargy).

Most of the time, a baby not opening wide to latch is just dealing with reflex coordination or positioning — not an emergency. But if you see these red flags, don’t wait. Call your pediatrician, IBCLC, or feeding support team so your baby gets help right away.

Not an Emergency, But Still Worth Checking

Some patterns aren’t dangerous, but they still mean your baby might need extra support:

• Only feeds with constant stimulation (tickling, undressing, prodding) after the first week.
• Feeds for just a few minutes before stopping, then won’t reopen to latch again.
• Hasn’t returned to (or close to) birth weight by 10 days old.

These don’t always mean something is seriously wrong — but they’re your cue to check in. The earlier you get guidance, the faster things usually improve.

So if your baby won’t open their mouth wide to latch, and you’ve ruled out emergencies, the next step is to understand what’s getting in the way of that wide-open reflex — and how things like positioning, sleepiness, or hunger can make all the difference.

Positioning to Help Your Newborn Open Wide to Latch

Newborns may look tiny and helpless, but when it comes to feeding, they’re surprisingly capable.

They’re born with reflexes designed to help them find the breast and open their mouth wide to latch — your role is simply to set the stage so those reflexes can work.

The key is positioning.

The gape reflex — the one that makes babies open wide — is triggered when your baby’s chin touches your body first, not their lips. If your nipple reaches their lips before their chin is planted, the cue to open wide gets cut off, and you’ll often end up with a shallow, painful latch.

If you were taught to stroke your nipple down your baby’s lips to get them to open, you’re not alone — that advice is common.

But it often leads to sucking instead of gaping, which makes feeding harder instead of easier.

Positioning to Help

If your baby isn’t opening wide enough to latch, the very first thing to check is positioning.

Getting the chin planted first gives their reflex a chance to fire the way it’s supposed to — and that’s the best place to start.

And even when positioning is spot on, there’s another big factor: timing. A baby who’s too sleepy — or already too hungry — won’t always open wide either.

Let’s look at what to do when your newborn is too sleepy to open wide to latch.

When Your Newborn Is Too Sleepy to Open Wide

Newborn sleep is like a spell — once they’re out, they’re really out. That kind of deep, floppy sleep can make it feel almost impossible to get your newborn to open their mouth wide enough to latch.

And here’s the paradox: feeding reflexes don’t work when your baby is deeply asleep. But if it takes so much effort to wake them that they’re frantic by the time you try to feed, those reflexes don’t work well then either.

It can feel like an impossible loop — calm but too sleepy, or awake but too upset. The good news? This phase doesn’t last forever. That heavy, impossible-to-rouse slumber is strongest in the early weeks, and as your baby grows, their sleep patterns gradually lighten and feeding often gets easier.

In the meantime, here are a few things that can help until it’s easier:

• If you swaddle, try gently removing it 20–30 minutes before feeding so your baby begins to stir earlier.
• Let your baby finish naps on your body, skin-to-skin, so their reflexes activate naturally before they’re fully awake.
• Offer feeds more often — every 2 to 2.5 hours — so your baby has a chance to use their reflexes before hunger tips into meltdown.
• If your baby is still sound asleep when it’s time to feed, don’t panic. Unswaddle and watch for a few minutes — little movements or eye flutters often give you the perfect window to try.

And most importantly? Give yourself grace. Sometimes your baby will sleep straight through, sometimes you’ll feed them in a barely-open state just to get everyone settled. That’s okay. Once the storm passes, you’ll try again — and each attempt gives you and your baby another chance to learn together.

And if your baby won’t open their mouth wide to latch because they’ve tipped past sleepy and into full-on crying?

That’s a different challenge — and we’ll cover how to handle that next.

Too Hungry or Crying Hard to Open Wide to Latch

Once your newborn is crying hard or frantic, their reflexes often shut down. Instead of opening wide to latch, they’ll close down and slurp—or (god forbid) chomp—your nipple into their mouth.

It might get milk flowing in the moment, but it usually hurts and keeps the latch shallow.

This doesn’t mean you’re doing anything wrong. It just means your baby is overwhelmed. You responded the best you could with where they were at in the moment.

Your baby’s nervous system simply needs a chance to calm before those gape reflexes can switch back on. That’s where skin-to-skin and gentle movement can be your secret weapons—both help reset your baby so you can try again.

• If you can calm your baby first, you’ll usually have better luck getting them to open wide for a deeper latch.
• If you can’t, it’s okay to latch them, let them settle while feeding, then unlatch and try again—if it’s not too painful for you.
• If your newborn flips from sleepy to screaming in 60 seconds flat, skin-to-skin with a gentle bounce can help bring them back to calm so you can try again.

Spending as much time skin-to-skin as possible in those first weeks makes it easier to catch your baby’s early feeding cues before they’re upset.

When they’re tucked against your chest, you’ll often notice little signs—bobbing their head, mouthing at your skin, even flinging toward your nipple—that show they’re ready to feed calmly.

And beyond helping your baby open their mouth wide enough to latch, snuggling your newborn on your chest?

Those moments are golden.

It doesn’t have to be you, either—anyone can help, as long as it’s bare skin on bare skin. That contact is what unlocks the magic.

If your baby won’t open their mouth wide to latch—whether from sleepiness, hunger, or overwhelm—remember: these are all just states you can work with. Next, let’s step back and talk about the bigger picture of why feeding a newborn is hard, and how you’re doing better than you think.

Feeding a Newborn Is Hard

The early days of feeding and caring for a newborn are an entirely new category of overwhelming.

If it feels like you don’t know what you’re doing… it’s because you probably don’t. Yet.

And that’s normal. Nobody knows what they’re doing at first. Parenthood is basically a crash course in learning on the fly, and your baby is just giving you the first lessons in real time.

The truth is, newborns are resilient, and their reflexes are built to help guide them—and you—along the way.

You’re not doing this wrong. You’re just in the middle of learning, and you’re probably doing better than you think.

If your baby is feeding well most of the time, gaining weight, and things are gradually getting easier—not harder—you’re right on track. And if they’re not?

That’s okay too.

It simply means there’s a reason behind why your baby isn’t opening their mouth wide enough to latch—and once you understand what’s getting in the way, you can make things better. Every feed is practice, and with the right support, feeding really does get easier.