By now you’ve likely learned to recognize the various types of crying your baby has. You can distinguish between the I’m-so-hungry cry and the get-me-out-of-this-soggy-diaper cry. Your finely tuned ear may also pick up the I-need-attention and cuddle-me-now cries.

Sometimes crying is accompanied by expressive body movements, including an arched back. Back or spine arching — like a bow or doing the cat pose in yoga — is common in babies. Babies arch their backs for many reasons.

In some cases, an arched back along with other symptoms can signal a health condition. But if your baby arches their back without any other symptoms, chances are they’re just a natural at yoga. Let your baby’s pediatrician know about the back arching, just to be on the safe side.

Here’s what to look for and what your baby might be trying to tell you.

Gassiness

Gassiness can be common in a baby’s brand new digestive system. Some babies can have bouts of fussiness that last for several day or weeks. This is sometimes labeled generically as colic.

Colic can start when your baby is only 4 to 6 weeks old and cause crying for hours at a time. Fortunately, babies usually outgrow colic by the time they’re 4 months old.

Your baby might arch their back when they have gas or an upset stomach. This could be because arching the back stretches the stomach a bit and might make them feel a little better. You might notice that your baby arches their back after feeding, when trying to poop, and even while lying down.

Baby reflux

Reflux, or gastroesophageal reflux, is common in babies right from birth to about 18 months of age.

Babies reflux happens because the round muscles that pinch both ends of the stomach closed don’t yet work properly in these new little humans. If your baby is premature, they might have more reflux.

Your (very healthy) baby can have reflux several times a day. It’s usually completely normal and nothing to worry about. But, sometimes if they’re spitting up and seem to have other symptoms, they may arch their back.

Similar to when babies have colic, they might arch their back because it helps bring down the feeling that come with reflux. You might notice this during and after feeding, while your baby is lying down, and even while they’re fast asleep.

Body language

Sometimes your baby might arch their back because they don’t want to be held or fed. This kind of body stiffening could be a sign to put them down or change position.

Some babies have strong back muscles and this may be the easiest way — other than crying — for their body to tell you what they want. Your little independent one may use the “back arch method” to get out of unwanted cuddles up to the age of 2 years! (Don’t take it personally, mom and dad.)

Startle reflex

Most babies have a startle reflex (also called the Moro reflex) when they hear a sudden or loud noise. It might also happen if they feel like they’re falling or if they’re moved suddenly.

Startling may make a baby suddenly straighten their legs forward and throw back their arms. Their head may also jerk backwards, making their back arch. The startle reflex usually goes away by the time baby is 2 to 4 months old.

Rollover attempts

As your little one gets used to tummy time, they’re also building stronger back and neck muscles. They’ve learned to lift their head and realize that the more they can move, the more they can look around. This is exciting!

So your baby may arch their back during tummy time or while they’re lying down on their side or back to get into a better position to explore. Some babies arch their backs when they’re trying to roll over or move forward. You’ll probably see their eyebrows go up as they wiggle every muscle they can.

Temper tantrums

Your little angel might have a head start on the terrible twos. Some babies arch their backs and throw their heads back when they’re upset or frustrated. This can happen while they’re lying down, sitting down, standing — or even cradling in your arms. A baby in the heat of a tantrum may also cry, whine, and thrash about.

Just about anything might set off a temper tantrum. Your little one may be hungry and not getting what they ordered from you — their short-order cook — immediately. Or they may be finished feeding and want to go play. Or your baby might be frustrated because they can’t express their needs to you.

No matter what the reason for a tantrum, it can be alarming when your baby arches their back and throws their head backwards. They can hurt themselves — and bump you squarely in the face.

If your little one gets into the habit of this, look for warning signs like crying or being upset first.

Seizures or seizure-like movements

Although it sounds serious, seizures in newborn babies aren’t the same as seizures or epilepsy in older children and adults. Your baby may have seizures — or seizure-like movements and behaviors that are mistaken for seizures — that begin in the first week of life.

A seizure can last for a few seconds. Your baby might suddenly be very quiet and look like they are very stiff or frozen. Or they may still be able to move their hands by rotating their wrists.

Some babies may arch their backs during what appears to be seizure-like behavior. It can happen at any time, usually when your baby is awake or just drifting asleep.

Newborn seizures are uncommon, but may happen because a baby’s brain is still growing and the nerves can get their wires crossed. One rare type of newborn seizures can run in families. Some babies with this rare genetic type of seizure disorder may have them often, while others have them once in a while or not at all. These baby seizures usually stop completely by the time your child is 6 to 9 months old.

Nerve damage

Your baby’s delicate neck and back can get sprained in a difficult delivery. Sometimes, the nerves between the neck and shoulders can get damaged.

Erb’s palsy is a condition that happens to about 1 out of every 1,000 newborns. It happens when the neck nerves are weak because of too much stretching during birth. The weaker nerves lead to weaker muscles in the neck and shoulder.

This may cause back arching in your baby, because they can move their back muscles and other strong muscles better than their neck muscles. However, back arching alone isn’t a sign of this condition. It would come with other symptoms — in particular, decreased movement in one shoulder and arm.

Most babies with Erb’s Palsy and other nerve damage from birth recover completely. Your baby’s pediatrician may recommend daily exercises to help make the neck and shoulder muscles stronger.

Newborn jaundice

Almost 60 percent of newborns have jaundice. This condition might make your baby look a bit yellow. It happens because a new baby’s tiny liver is not yet working properly, which causes too much bilirubin in the blood. This chemical is left over from when your body breaks down blood.

Babies have the most bilirubin when they are 3 to 5 days old. Normally, the liver kicks in and clears up the bilirubin by the time your baby is a couple of weeks old.

Sometimes, the jaundice gets worse instead of better. In rare cases, too much bilirubin, causing severe jaundice, can cause a kind of brain condition called kernicterus.

Arching the back is a classic sign of brain damage from kernicterus in babies who have or have had very high bilirubin levels. Other symptoms include:

  • high pitch crying
  • floppiness or stiffness
  • hard to wake up or not sleeping at all
  • not feeding well

This serious condition only happens if the jaundice isn’t treated and bilirubin levels get very high. If your baby is diagnosed with kernicterus, they can still be treated by a specialist doctor.

Cerebral palsy

Cerebral palsy is a group of muscle control conditions. It usually happens when there is brain damage while your baby is still in the womb. About 1 in 323 children worldwide have a type of cerebral palsy.

Signs of this condition might show up while your little one is a baby or toddler. Signs include muscle floppiness, strong reflexes, and stiffening (like arching the back). Babies with cerebral palsy may also have trouble swallowing and moving their eyes. Some babies with this condition may also be more likely to have seizures.

Sandifer syndrome

Sandifer syndrome is a rare movement condition almost always associated with gastroesophageal reflux disease (GERD). It starts in babies or small children. Once the baby is treated for GERD (or it goes away on its own), this condition goes away.

Sandifer syndrome causes serious back arching in babies that can last for up to 3 minutes. It causes a frozen kind of back arching that can sometimes be mistaken for a baby seizure.

Back arching from this syndrome can happen about 10 times a day, usually after your baby has eaten. During back arching your baby will also stretch their legs out backwards and be very stiff. Other symptoms of Sandifer syndrome include:

  • tilting the head to one side
  • nodding head movements
  • poor feeding
  • vomiting
  • problems with eye movements

Children with autism spectrum disorder (ASD) typically show several signs. This sometimes includes repetitive motions like back arching, but remember that back arching is much more often due to other causes.

Autistic children may show symptoms around the time they are a year old (or earlier), but most kids aren’t diagnosed until they’re about 3 years old.

A newborn or a baby that is only a few weeks to a few months old will likely not show signs of this condition. If your child is on the autism spectrum, they’ll likely have several other signs along with back arching.

By the end of the first year, an autistic baby may show characteristic traits that are more common, like:

  • not smiling spontaneously at parents or caregivers
  • not using eye contact to communicate
  • not gesturing (waving or pointing) on their own

Later on your child may show other repetitive motions, such as:

  • stiffening their arms
  • flapping their hands
  • walking on their toes

In most cases, your baby’s back arching will go away on its own as they learn to roll over and control their body better, outgrow the startle reflex, and get more comfortable with people around them.

If there’s a health problem that’s making your little one arch their back, treating the underlying condition will solve the back arching. For example, treating common baby problems like gassiness and acid reflux will take care of the back stretching.

For normal gassiness and baby reflux you can try simple, low risk home remedies like:

  • prop your baby upright after feeding
  • avoid overfeeding
  • give smaller feeds more often
  • use a smaller bottle and nipple size to stop air-gulping if this seems to be an issue
  • thicken breast milk or formula with a tiny bit of infant cereal (check with your pediatrician first as this can have risks)

If your little angel is throwing their head backwards and arching their back in a toddler temper tantrum, gentle behavior training may help stop this. Teaching your child how to express themselves in a less dramatic way might help. Ask your pediatrician for recommendations.

Some babies with seizures will naturally outgrow them. Other more serious causes of back arching may need physical therapy, medications, surgery, or other medical treatment.

Sometimes gassiness and fussiness can start to be accompanied by other symptoms that won’t go away, and acid reflux might be a sign of a more serious health condition. Call your child’s pediatrician urgently if your baby:

  • is crying for 3 hours or longer
  • is arching their back and showing other signs of pain
  • throws up every time you feed them
  • is irritable during feeding
  • refuses to feed
  • isn’t gaining weight or has lost weight
  • isn’t wetting their diaper

Look for symptoms of brain or nerve problems along with back arching. Contact your child’s doctor or go to urgent or emergency care right away if your baby experiences:

  • sudden difficulty latching or feeding
  • weak sucking
  • difficulty swallowing
  • high-pitched cry
  • seizures
  • bulging or swollen soft spots on the head
  • stiffness
  • floppiness
  • strange head or neck posture
  • jerking movements
  • muscle spasms

If your baby’s got back (arching), you probably don’t have to worry. Babies arch their backs for many reasons — or for no reason at all. In a happy, comfortable, healthy baby, back arching likely has no cause and is just one of those things they do.

This common baby movement can also be a sign of other underlying health problems — sometimes serious. If you notice your baby is arching their back, look for other symptoms. Let your pediatrician know what you notice. Make sure you take your new bundle of joy to all their regular check-ups.