Young women who binge drink will be told this week that they risk a sharp rise in the number of children born with birth defects.

As the 'lager loutette' generation begins to settle down and have families, campaigners are urging more draconian health warnings against drinking during pregnancy.

By the end of the year the French government will follow the example of America by demanding that warning labels are put on all bottles, spelling out that alcohol may cause birth defects.

Ross Cranston, the former minister and chairman of the all-party parliamentary group on alcohol misuse, will host a House of Commons meeting this week to highlight foetal alcohol syndrome (FAS), where heavy drinking during pregnancy can lead to serious developmental disorders in the baby.

He said the rise in women drinking heavily had alarming potential consequences,: 'If they don't yet know they are pregnant and so carry on binge drinking, it's a worry. We have not taken this problem seriously in this country.'

The all-party group has campaigned for labelling.

In the US pregnant women are advised not to drink at all: the French public health minister has also signalled plans to put warning labels on alcohol bottles and cans.

It follows legal action taken against the state by three mothers from Lille whose children have congenital deformities. They say that they were not told enough about the consequences of drinking when pregnant.

Benoit Titran, the lawyer who runs the group representing the mothers, argues that Britain should start to give women far more information about what drink can do to the foetus.

The official advice to mothers-to-be in the UK is that they can drink one or two units a week. While it is universally accepted that heavy drinking in pregnancy can cause a recognised syndrome - FAS children typically have distinctively shaped skulls, eyes and upper lips, along with low IQs and behavioural problems - there is debate over whether 'social' drinking is harmful.

The National Organisation for Foetal Alcohol Syndrome, a charity set up in the UK last year, argues that there is growing evidence that milder problems such as hyperactivity could be linked to relatively low levels of drinking during pregnancy.

However, Dr Moira Plant, director of the Alcohol and Health Research Trust at the University of the West of England and an adviser to the World Health Organisation, said there was little evidence.

She added: 'If you don't drink, you are guaranteed to have no harm to your baby, of course. But if one glass of wine harmed your baby, you would have an amazing number of damaged babies around.

'If someone is pregnant and has been for 10 weeks before realising it, I would think the stress of saying "one drink is going to damage your baby" is more damaging than that one drink.'

The number of cases of FAS diagnosed in the NHS is small but it has risen from 95 in 2000-01 to 128 in 2002-3.

However, Jane Ellis - not her real name - argues that young women should be told not to drink at all if they are pregnant or thinking of conceiving. Her six-year-old adopted daughter has FAS. It was only when she started school that the extent of her problems became apparent. After two years, while she has no problems with maths, she can read only a few words.

She said: 'The important thing is to stop drinking as soon as you know you're pregnant. Life with an FAS child is very hard; it affects the whole family. It's not worth the risk.'