Are long car journeys safe for newborn babies?Lab-based study gives cause for concern

05 October 2016

Kiddy-Luna-iSize 2

Kiddy Luna i-Size creates a lie-flat position in the car

Newborn babies may be at risk of breathing difficulties if left in car safety seats for long periods, particularly when the car is moving and the seat is at an upright angle, according to new research. 

Babies in the lab-based study showed 'significant signs of potentially adverse cardiorespiratory effects' when seated upright at a 40 degree angle, particularly when the movement of a car was simulated.

At Which?, as well as crash testing each car seat we review, our car seat experts also assess the angle of each car seat they see. Any car seats which are too upright can be downgraded in our tests.

If you're looking for a car seat for your new baby, make sure you get a Which? Best Buy child car seat.

Are child car seats safe for long journeys?

The research was a pilot study carried out by Great Western Hospital NHS Foundation Trust in collaboration with the University of Southampton and the University of Bristol. Researchers said that a larger study will be needed to investigate the significance of the results.

To mimick the effect of being in a moving car, the study designed a simulator to reproduce the vibration similar to that of a rear-facing car seat in a car travelling at 30 mph. 19 healthy newborn babies and 21 premature babies were monitored while lying flat in a cot, in a seat at 30° and 40° degree angles, and again in a seat at a 40° degree angle with added vibrating motion. 

The research was funded by the Lullaby Trust, a charity that provides advice on safer baby sleep and raises awareness of sudden infant death syndrome.

Advice on babies and car seats

Which? child car seat expert Lisa Galliers said: 'This pilot study supports the long standing advice given by many car seat experts, that it's best to avoid keeping babies, particularly very young ones, in car seats for any longer than absolutely necessary. 

'Naturally, parents will need to take long journeys from time to time. Regular breaks are recommended in these cases - or you could look for a baby car seat which holds your baby in a flatter position.'

Car seat manufacturers are tackling this issue already. Kiddy, for example, has launched the Evo Luna i-Size, which has a built-in recline so you can lie your baby in a flatter position while in the car. 

Cybex’s Cloud Q car seat has a similar function, but it can only be used in this way when on the chassis of a pushchair.  

Britax is about to launch its first i-Size infant carrier, which is compatible with its Flex base. You can adjust this base to the angle of your car's seat, helping to keep the baby seat at the correct angle.

We've tested the Kiddy Luna i-Size and the Cybex Aton Q already. To see how these types of child car seats perform in our safety tests, visit our child car seat reviews

Which? child car seat testing

Our experts have specially designed the crash tests we put each seat through, making them more demanding than the legal minimum standard requires, and feel our tests more accurately reflects what may happen in a real crash. We also include a side impact crash test, something that's only just been introduced into the latest car seat regulations (R129).

The best child car seats, properly fitted, will help keep your baby protected and cushion a collision whether it's frontal-impact or on or a side-impact. The worst could leave your baby at higher risk of serious injury if you're involved in a crash.

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