Dr Penelope Leach says recent scientific tests show high levels of the stress hormone cortisol develop in babies when no one answers their cries.
If this happens over long periods and repeatedly, it can be “toxic” to their brains.
Leach (pictured) suggested unattended extreme crying bouts of 30 minutes or more could be damaging to babies.
Dr Leach told the BBC News Website: “We are talking about the release of stress chemicals. The best known of them is cortisol, which is produced under extreme stress.”
“One is not talking about a wakeful baby lying there gurgling, one is talking about a baby that is crying hard and nobody is responding.
“When that happens, and particularly if it happens over a long period, the brain chemical system releases cortisol and that is very bad for brain development.
However, research published last month found no ill effects on children whose parents had used “controlled crying” when they were babies.
The study by the Murdoch Childrens Research Institute in Australia, followed 225 six-year-old children who had received behavioural sleep intervention as babies to assess their health – including emotional wellbeing, behaviour and child-parent relationship.
It found techniques such as “controlled crying” had no adverse affects on the emotional and behavioural development of children or on their relationship with parents.
Anastasia Baker, (pictured) director of Night Nannies, which helps solve babies’ sleep problems thinks there isnt any harm in leaving a baby to cry for a few minutes.
‘If the baby is over six months and on solids, has been winded and fed and there’s no reason for it to be crying then our troubleshooters will be to leave babies for a few minutes, then go back and reassure the baby then leave to them for another few minutes.
There is no harm in it and it can be a really useful way of getting a baby to learn to go to sleep on its own.
So many mothers make the mistake of letting the baby fall asleep on them while feeding and the baby never gets used to going to sleep on its own. We have had clients who have had to rock their child to sleep for literally hours. That is no way for that family to live.’
Mandy Gurney, founder of Millpond Sleep Clinic, added: “Obviously no one would advocate leaving a child to cry for long periods. But I think you can leave a child for a few minutes before going in to reassure them. Research has shown that using these techniques to tackle a sleep problem can have a very positive effect on family life.”
Studies have suggested that up to half of parents have problems with their child’s sleep patterns between the ages of six months and a year. In some cases this can lead to marital problems, family breakdowns, behavioural problems and maternal anxiety.
So where what are we to do? do we let our babies cry a river, or do we give into their demands? I think its all about balance- recognising your babies cry, understanding their needs and responding accordingly.
Yes of course it’s o.k for your baby to cry and to be left to cry, if this is done in a controlled* way, returning every few minutes to reassure and to comfort.
Anyone with any common sense knows that you can’t leave a baby crying for long periods of time with no attention, and this is where Leach is coming in with her claims of brain damage.
Babies need love, attention and support, but they also need to learn to settle themselves.
This technique teaches babies and toddlers to fall asleep independently.
Controlled crying means checking on your child at set intervals, increasing the time between visits until they fall asleep.
Put your baby in the cot and leave the room. Return after two minutes gently whisper ‘sleepy time’ stroking their tummy for two minutes, then leave. The idea is not for you to get your child back to sleep but to reassure yourself and your baby that all is well.
Increase the interval between visits by two minutes each time, starting with two minutes and going up to a maximum of 15 minutes.
Repeat the checking every 15 minutes until your child quietens and goes to sleep. Apply this technique at bedtime. Repeat it every time the child wakes up.