More than half of women drink alcohol while pregnant despite growing evidence that it can lead to low IQ, attention deficit disorders and more serious lifelong complications in children.
Older mothers are more likely to drink while pregnant than younger ones, the latest figures from the National Health Service show.
This has lead experts to fear the number of damaged children will grow as more women put off having a family.
Children born to mothers who drank while pregnant are more likely to grow up to have alcohol and drug problems, be excluded from school and have antisocial behaviour problems.
More than 8,500 under 18s were admitted to hospital because of their drinking in 2006/7 it was revealed on Thursday and a proportion of those are likely to have some degree of brain damage because of their mother’s drinking, experts said.
High flying women working as stockbrokers and traders in the City have called charity helplines after their children were diagnosed with Foetal Alcohol Spectrum Disorder, along with wives of MPs and members of the House of Lords, showing the problem is increasingly associated with middle class drinkers.
Damage to the child increases with the amount of alcohol drunk and the timing during the pregnancy. The full blown Foetal Alcohol Syndrome is the leading known cause of non-genetic intellectual disability in Western countries and causes severe learning difficulties, impaired intellect, certain facial characteristics and growth retardation.
Less severe damage is associated with hyperactivity, poor memory and planning skills, poor co-ordination and lower IQ, but this is often not recognised as associated with maternal drinking.
Last year the Department of Health revised guidelines to say women should not drink at all during pregnancy but if they choose to they should stick to one or two units once or twice a week and not get drunk.
Figures released by the NHS Information Centre revealed that 55 per cent of women in the UK admitted drinking alcohol while pregnant.
Of the women who drank before they conceived, only a third gave up alcohol altogether while pregnant and the rest said they cut down.
The survey also found 61 per cent of mothers aged 35 or over said they drank while pregnant compared to 47 per cent of those aged under 20.
Older mothers were also less likely to give up alcohol while pregnant.
Susan Fleischer, director of the charity National Organisation for Feotal Alcohol Syndrome, said women in powerful and male dominated careers had been calling their helpline after their children were diagnosed with the disorder.
She said these women were not alcoholics but had a regular habit of drinking with male colleagues and found it harder to stop while they were pregnant.
Ms Fleischer, who has an adoptive daughter with the condition, said: “Not all women who drink during pregnancy will harm their child but the only way to be sure is not to drink at all.
“Some of the children being admitted to hospital because of their own drinking will have brain damage caused by their mother’s drinking and there will be a smattering of middle class kids in there too.”
Survey by the charity Tommy’s in 2004 found one in four pregnant women drink between two and five units of alcohol a week, double the recommended weekly limit.
Reliable studies on the numbers of babies born affected by alcohol have not been carried out in the UK but in other European countries and in America and Canada it is estimated that between 20 and 40 children per 1,000 have feotal alcohol spectrum disorder and fewer have the full blown syndrome.