Delivering a premature baby is a harrowing experience, to say the least. Instead of the peaceful transition into parenthood that everyone hopes for, preemie parents may be looking at separation from their newborn baby, a long NICU stay, scary health events, and complicated medical interventions. It’s an overwhelming thing to deal with! And whether your little one spends ten days or 110 days in the NICU, one big milestone that almost all soon-to-be NICU grads (and even some well-born babies!) need to check off their to-do list is the Car Seat Test. 

Newborn Car Seat Test

What is the Car Seat Test?

The Car Seat Test, also known as the Infant Car Seat Challenge or Angle Tolerance Test, is an important screening to make sure that a baby can safely sit in their car seat without having any dangerous problems with their breathing, heart rate, or oxygen. 

Who needs a Car Seat Test?

The American Academy of Pediatrics recommends the Car Seat Test for all babies born before 37 weeks or born weighing less than 5lbs 8oz (2500 grams) — yes, many younger and smaller babies get to avoid NICU time. But they should still have a car seat test before discharge from the postpartum floor. Even if they are born after 37 weeks and weigh more than 5.5 pounds, babies who need to go to the NICU for certain types of breathing problems at birth should also have a Car Seat Test. NICU doctors or pediatricians may order a Car Seat Test for other less common reasons, as well. 

The reason these babies need a car seat test is because they are at risk for breathing problems when they’re sitting semi-upright like they do in a car seat. The test makes sure that baby will be able to breathe safely on their first ride home and beyond! 

What happens during the car seat test?

During the car seat test, buckle the baby into their car seat and sit there for a while. A medical monitor will track their breathing, heart rate, and oxygen saturation. As long as their vital signs stay in the normal range for the entire test, the baby passes. That’s it! 

Most of the time, the car seat test lasts 1.5 or 2 hours. Though some hospitals will have slightly different protocols. For example, if you live more than two hours from the hospital, your baby may have to stay in their car seat for the entire length of your drive home just to be extra sure! 

So… What’s the big deal?!

The car seat test sounds easy enough, right? Buckle baby in and wait. 

Of course, it’s not quite that simple. It’s important to make sure that the car seat test is set up correctly. The baby needs to be harnessed properly — meaning the harness should come from at or just below the baby’s shoulders. And the harness should be tight enough to pass the pinch test. And the car seat needs to be resting at the correct angle too! These factors help little ones protect their airway in their car seats. And if one of these factors is not correct, then the baby might have trouble breathing and fail the test. 

But don’t worry! There are lots of things parents can do to help their baby pass their car seat test. Here are some tips from Safe in the Seat’s NICU-based CPST (Child Passenger Safety Technician)!

How to Pass the Car Seat Test

Get to know your car seat.

Before you bring your child’s car seat into the hospital for their car seat test, read the manual cover-to-cover. Take note of infant insert rules, low birthweight harness routing, and any adjustments that you need to make for your child’s size. Go ahead and make these adjustments if you can! (Oh, and here’s another tip: if your car seat includes optional shoulder padding on the harness, go ahead and remove the pads now and store them somewhere safe. They’re usually in the way for newborns. But they’ll be useful to protect your baby’s neck when they’re a bit bigger!)

Ask for a CPST.

In most hospitals, the default person responsible for a baby’s car seat test will be a registered nurse. And if you’ve been around Safe in the Seat for a while, you’ve seen me talk about how RNs — as amazing as they are — aren’t usually car seat experts! Default job training for neonatal and pediatric nurses does not usually include technical car seat education. Your child’s nurse may happen to know the basics of proper harnessing… but she also might not. Nurses may also use inserts incorrectly or miss required weight-based harness changes. Don’t be afraid to ask if there is a CPST on staff who can start your baby’s car seat test to make sure that everything is correct and your little one is set up for success! 

A fed baby is a happy baby.

The car seat test should start soon after baby finishes a feeding. If your little one has reflux issues, you can hold them upright for 15-30 minutes between feeding and testing. But aim for a start time as close as possible to the end of that snack. Do one last diaper change before buckling, too. This way, baby will be comfy and (hopefully!) happy during the entire test.

Be present for your baby’s car seat test — at least at the beginning!

Whether your hospital has a CPST on staff or not, ask your child’s healthcare professional team if you can be there when your baby’s car seat test starts. This way, you can make sure that your baby’s harness fit is perfect. And you can see exactly how baby was positioned and buckled. It’s important to recreate the same setup when driving because changes in harness fit, insert use, or recline may affect the child’s ability to breathe.

Leave baby alone.

Once the car seat test starts, do your best to leave your little one alone. I know, I know — easier said than done! But it’s important to assess baby’s independent ability to safely sit in their car seat. Even in varied conditions such as fussing, spitting up, or sleeping. Once the clock starts, it’s a great time to sit down with your book or your latest Netflix binge. Or maybe step away for a stroll and a snack. The timer will sound before you know it! 

Recreate going-home conditions as closely as you can.

If you’re taking your little one home with a feeding tube, oxygen cannula, cranial helmet, or any other medical equipment, their car seat test should include these items! For example, a baby with a feeding tube who will need to be fed during car rides can (and should!) be fed like normal during their car seat test. It’s important for the car seat test to closely replicate the way baby will actually be riding in the car. And medically fragile kiddos going home with extra support should have these needs considered during their car seat test.

What if baby fails the car seat test?

If your baby fails their car seat test — if their oxygen or heart rate drops and doesn’t recover quickly enough — don’t panic! Here are some steps you can take next. 

Ask about hospital policy.

Different hospitals have different approaches for babies who fail their first car seat test. Ask how many more chances baby will get to pass the test and how much time must pass between attempts. 

Double-check baby’s harness fit.

This is important, especially if you couldn’t be present to verify baby’s harness fit during the original test! There is always a chance that something isn’t quite right. Make sure that the harness height, crotch buckle setting, and any other seat-specific adjustments — like harness length or hip strap settings — are correct. 

Learn Proper Harnessing

Assess those inserts.

Does your baby’s car seat have a head insert or a staged body insert? If so, consider your options for insert use within the manual’s rules. Sometimes, inserts do more harm than good when it comes to baby’s positioning! If allowed, it can be beneficial to remove the head insert in some infant car seats to allow baby to maintain a neutral airway position. If you can, choose a low-pressure time to assess baby’s fit and head position with and without optional inserts to figure out what looks best before their next test attempt.

Fill in the (crotch) gaps.

Check how much space there is between your baby’s body and the crotch buckle of their car seat. This is one of the biggest problem areas for tiny babies in their car seats — a big gap between baby and buckle can allow your child’s hips to slouch down and forward over time, resulting in dangerous chin-to-chest positioning. Many infant car seats allow a crotch roll, which is a rolled washcloth placed in between baby’s diaper and the crotch buckle after you harness your child in. This intervention can prevent that problematic slouching, and it can make a huge difference in overall body positioning!

Newborn Car Seat Test
Newborn Car Seat Test

Note: Not all car seats allow a crotch roll, so check with the manufacturer or with an experienced CPST before you jump on this trick.

Add some (safe) torso support.

Most of the time, a crotch roll is enough to fix a slouchy posture in the car seat, so that’s the first thing we’d try. But sometimes, the baby needs side support to help the little one breathe easily in their seat. Many infant car seats allow caregivers to add tightly rolled receiving blankets on either side of their child’s torso after the child is fully, safely buckled. If you need to use this trick, keep in mind that your goal is torso support, not immobilizing baby’s head! Baby should be able to move their head in their car seat. But a well-supported torso can help with airway alignment and overall positioning in the seat.

Note: If your child’s car seat has its own body insert, using that is usually the first choice. If you need to use rolled blankets, the car seat’s own insert should usually be removed so that the blankets + insert combination doesn’t cause positioning problems. 

To safely add torso support, tightly roll 2 receiving blankets and tuck them alongside baby’s torso in the car seat. Preferably, the blankets shouldn’t go higher than ear level — we don’t want to add a suffocation risk if baby turns their face into a soft blanket! 

infant incorrect support
baby incorrect support
baby correct car seat safety

Never use blankets, unregulated (aftermarket) inserts, or other materials to immobilize a baby’s head. 

Give it time.

The home stretch of a NICU stay can be the hardest part. Baby is healthy and doing well, eating, and gaining weight, and you just want your little one home! But sometimes, a couple more days of growth and rest can be all a baby needs to pass their repeat car seat test. If you’ve made sure that baby had a good harness fit and decent overall positioning in their car seat, yet they still failed, then waiting a day or two before trying again can be a really helpful strategy. Maybe baby just wasn’t ready for hospital discharge yet. I promise time can make all the difference! 

Consider a different infant car seat.

Some car seats just don’t position little airways well. And this can be a huge issue for preemies or smaller-term babies! Understandably it’s a big decision to steer sideways and obtain a whole different car seat for your baby, which is why this option is near the end of this list. Most babies can pass their car seat test in most car seats! But if you’re worried about baby’s positioning in their seat, or if they’ve failed multiple car seat test attempts, you may consider choosing a different seat that’s known to provide excellent head and airway positioning for the tiniest passengers. Here’s our list of the best car seats for preemies!

Think about a car bed.

Rear-facing is the safest way for babies to ride. However, if you’ve exhausted all your options and your baby just cannot handle sitting up in their rear-facing infant carrier type of car seat, then a car bed might be needed to get them home safely. Car beds allow medically fragile babies to ride lying down. And they’re installed sideways across two vehicle seats in the back of your car. Because car beds are a downgrade in crash protection compared to rear-facing car seats, this option should be a last resort, and babies who need car beds should only ride in the car for medical appointments. Those fun outings or routine errands with your new addition will need to wait a while.

Some hospitals offer loaner car beds for their patients, either on their own or through a local DME company. Some families may be left to obtain a car bed themselves. And in this case, the Safety 1st DreamRide car bed is usually the most accessible option. Read more about car seats for premature babies on our blog.

If your baby is discharged in a car bed, ask the hospital about next steps before you leave. A repeat car seat test should be scheduled for 4-8 weeks away; this repeat test may be done at the hospital or at an outpatient pulmonology or general pediatrician’s office. 

The car seat test is a huge milestone that comes near the end of a baby’s NICU stay. And the process can be daunting, especially when it’s one of the last things to stand in the way of your baby’s discharge. But it doesn’t have to be a scary event!

With these tips, you can help your baby pass their car seat test and ride home safely. Soon enough, the NICU will be in your rearview mirror. Congratulations! 

If you’re still looking for more information to take you all the way from which car seat to buy through how to use it properly, check out our course and buying kit on infant car seats or schedule a virtual consult with us. And don’t forget to follow along on Instagram and YouTube for more car seat safety tips and tricks!

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