Women should not drink alcohol during pregnancy, a health watchdog has said, after changing its advice on how much is safe to drink.

Last autumn the National Institute for Health and Clinical Excellence (Nice) said it was fine for women to drink the equivalent of a small glass of wine daily after the first 12 weeks of pregnancy.

However, this draft guidance has been dropped and Nice is now saying women should avoid alcohol but, if they choose to drink, they should have no more than one or two units once or twice a week.

The watchdog said there is no fresh evidence to support its stance, which will see its views more closely aligned with those of the Government.

In May last year, the Department of Health advised that pregnant women and those trying to conceive should cut out drinking altogether.

Women who do choose to drink after the first 12 weeks should have no more than one to two units of alcohol once or twice a week and should not get drunk, it said.

Nice's new guidance echoes this and says women should not binge-drink (defined as more than 7.5 units on a single occasion).

Women are told to avoid drinking in the first three months of pregnancy because there may be an increased risk of miscarriage.

Drinking heavily in pregnancy can cause foetal alcohol syndrome, which may leave children with behavioural or learning problems.

Dr Gillian Leng, Nice's implementation systems director, said she did not think Nice and the Department of Health are sending out mixed messages.

She said both advised that "women should ideally be advised not to drink" but there was "no evidence" of harm to the baby from one or two glasses of wine a week.

The Government's Chief Medical Officer, Professor Sir Liam Donaldson, said he welcomed the updated Nice guidance as it strengthened the message that pregnant women or women trying to conceive should avoid drinking alcohol.

He said: "Nice's guidance highlights this is most important at the beginning of pregnancy, when there may be an increased risk of miscarriage, and again reinforces that if they do choose to drink, to protect the baby, they should not drink more than one to two units of alcohol once or twice a week and should not get drunk."

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