Slings, pram-bikes, vibrating rocking cradles …

It’s hard to keep up with trends in child-rearing paraphernalia. When I bought a car seat for my first child, for example, there was hardly any choice. Most products were variations on a curved seat that put the infant in a sitting or flopping position. Now the new “must have” accessory is a car bed, a more rigid kind of affair which straps the child in so that he or she is flat.

Fashion for babies is a curious thing, often faddish and needlessly expensive. However, in the case of car beds, there seems to be evidence to suggest that the reclining baby is healthier than its propped-up counterpart. But is this enough for us to make the switch?

A recent paper in the US journal Pediatrics sought to find out if the change in position would lead to a significant difference in the babies’ oxygenation. The researchers analysed the oxygen content of blood in two-day-old babies when in normal cribs, car seats and car beds. The theory was that car seats would be worse because the baby’s head can sometimes fall forward, preventing the infant from getting the usual amount of oxygen to the lungs. In practice, the babies in the crib had the highest oxygen content, at an average of 97.9 per cent, followed by those in the car bed, at 96.3 per cent, and car seat, at 95.7 per cent.

Does this matter? It may do if your baby was born prematurely or has other developmental problems that impair breathing or oxygen intake. In the US, the American Pediatric Association recommends that babies born at less than 37 weeks’ gestation should be considered for a test – usually using a clip-on probe – to make sure oxygen levels are stable when using a seat or bed. However, they and other researchers have stressed that more detailed research is needed in this field.

Indeed, it is important to note that there was a fall-off in oxygenation for babies placed in both types of car transport device. It is also difficult to know what the fall-off in oxygen means. Research suggests that frequent episodes of low oxygen may have an impact on development, but the exact correlation between car seats or beds and this type of problem remains unclear. It is true that many people use these devices to let the baby sleep in the house. Perhaps it would be better simply to use them only in the car, and to let babies sleep instead in their cot, cradle, Moses basket or whatever the latest trend is dictates.

Margaret McCartney is a GP in Glasgow
margaret.mccartney@ft.com

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