Holding your baby while they wiggle and squirm with general irritation is admittedly frustrating, but when they're so mad they start the dreaded back arch, all bets are off. They're screaming, you're upset, and it's one big power struggle. The answer to why babies arch their backs when mad is a multi-faceted one, pediatricians say.
"There aren't many things a baby can do by themselves at a young age, but they can muster up a forceful cry. Babies use the cry for communication and many go all out when making that statement," pediatrician Dr. Jarret Patton tells Romper. "They tend to use all of their muscles to get attention and a solution to their problem; back arching can be a part of the muscle recruitment that occurs."
Maybe your baby is at a point where they have figured out that they don't like their car seat. They've realized that once you put them in, they fall asleep, and they miss out on watching the world fly by out the window. Or, they realize that once in their seat they can't see you anymore. Either way, they don't like it and they're mad. Like, really mad. So they go all stiff like a surfboard and throw their head back with a vigorous arch any time you try to buckle them up. The struggle is real.
Crying is how babies communicate their needs, but why the back arch? I reached out to pediatrician and parenting expert Dr. Jennifer Trachtenberg who explained that babies arch their back when mad "most often to get their needs met and can't communicate by talking — the physical movement of arching back, flailing arms shows they are upset, angry, tired, or hungry." Dr. Jen, who also serves as a SpokesDoctor for the American Academy of Pediatrics, also notes that this is not the case with every baby, and "there are medical reasons such a gas, reflux, colic, and rare but also neurologic issues like seizures, or Cerebral palsy."
Aside from frustrations that occur as a result of outside factors like being uncomfortable in a car seat or being held in a way they don't like, babies may be arching their back when mad about something happening inside of their body. Just like you might double over and hold your stomach when it hurts, your baby may arch their back when experiencing internal distress.
"Back arching isn't always innocent," Dr. Jarret explains. "It could indicate a neurological problem or even a gastrointestinal problem like reflux. If your infant is arching when they are not crying, it is a good idea to make an appointment with your pediatrician. It is always helpful to bring in a video of the motion to aid in the diagnosis."
Having a video on-hand to show your pediatrician may help them see the back arching first-hand and provide clues as to whether this act is one of typical baby frustration and anger, or if it points to some deeper medical issue.
Dr. Jen recommends bringing your baby's back arching to your pediatrician's attention "if it's constant, they're not feeding well, very frequent arching with developmental delay, or anytime you have concerns."
Assuming that your baby is simply arching their back out of anger and everything medically checks out OK, Dr. Jarret suggests that parents can try to comfort their baby. "Swaddling or rocking is a great way to soothe the agitated infants," he tells Romper.
Additionally, Dr. Jen says that closeness and distraction can work wonders for an upset baby. "Often bring baby to a calm and quiet area, rock, cuddle, and hold baby close to you. If that doesn't help, distractions with music and/or a favorite toy just may do the trick," she tells Romper.