The truth about baby breathing monitors

Anyone with a very young baby knows what it feels like to spend half the night checking whether he or she is still breathing. What better way to allay anxieties and get some sleep than by buying a baby breathing monitor?

The latest of these, called the Baby Alert, is to be marketed later this year, price pounds 50. It has a special microphone to be placed under a cot mattress, which sends out an alarm if the child's heart stops beating for four seconds, or if breathing fails for 15 seconds.According to one recent newspaper report, the alarm, has been shown to "wake the child and prompt breathing", and could dramatically cut the number of fatalities from sudden infant death syndrome, or "cot death".

A number of similar electronic devices to monitor breathing are already on the market, designed to calm parental anxieties about cot death. Some are attached to the baby's tummy; others, like the Baby Alert, use a special pressure pad or mattress, while one wall unit beams out ultrasound waves above the cot.

All these devices work by detecting changes in breathing movements in the chest and abdomen. When breathing stops for longer than a pre-set time (usually 20 seconds), an alarm will ring and a light start to flash. Some monitors also measure temperature and heartbeat.

All of which may sound tempting to worried parents. But paediatricians say it is quite normal for babies to stop breathing for intervals of 20 seconds or more and then begin to breathe again spontaneously, so a device that triggers an alarm, (especially if it goes off at 15 seconds) may be creating unnecessary anxiety in the parents rather than detecting any real threat to the child. If a baby is in genuine collapse, a monitor will not save its life; parents need to be trained in resuscitation techniques.

False alarms from temperamental monitors are a common problem; a recent survey by Which? magazine found that seven out of ten mothers had switched the monitor off after repeated false alarms.

Breathing monitors can, on the other hand, create a false sense of security. They do not detect "obstructive apnoea", where breathing movements continue but an obstruction in the windpipe prevents any oxygen reaching the baby's lungs. And the alarm may be prevented from going off when it should, by other body movements unrelated to breathing.

Some parents may end up being psychologically dependent on a monitor, to the point of being frightened to go anywhere without it.

Nor is there any evidence that using a monitor will prevent cot deaths; in Germany, the US and Belgium, where the use of monitors is widespread, cot death rates have not fallen. Some research has found cot deaths to occur in babies who had monitors attached. The mechanism of cot death, and its relation to apnoea (when air flow into the lungs stops), is not yet established; it may be that sometimes breathing stops only because the baby is dead already.

That said, a high quality monitor can be useful, with professional support, in cases where babies are considered to be at high risk: if they have previously stopped breathing for a lengthy period (known as an apparent life-threatening event, or ALTE); or if there has already been a cot death in the family. Cot death is the biggest killer of babies under one year old; small wonder that new parents are so terrified of it. The best ways to reduce the risk are to stop smoking in pregnancy; put the baby on its back to sleep; avoid smoky rooms; prevent overheating the baby; and keep the baby's head uncovered

Cherrill Hicks

For further information contact the Foundation for the Study of Infant Deaths helpline (0171-235 1721). The Cot Death Society (01635 861771), a registered charity, loans out monitors to parents of babies at risk.