Drinking during pregnancy could become a crime following the outcome of a current court case, women's charities say.
A council in the North West of England is seeking criminal injuries compensation after a six-year-old girl was left with growth problems caused by her mother's alcohol consumption during pregnancy.
If the Court of Appeal agrees the woman committed a crime, the British Pregnancy Advisory Service (bpas) and Birthrights claim it could pave the way for pregnant women's behaviour to be criminalised.
The little girl was born with Foetal Alcohol Syndrome (FAS), which can cause growth and facial abnormalities and intellectual impairment.
A written ruling by the Upper Tribunal of the Administrative Appeals Chamber said it was a ''direct result'' of her mother's drinking.
But it concluded: ''If (the girl) was not a person while her mother was engaging in the relevant actions then... as a matter of law, her mother could not have committed a criminal offence.''
Lawyers for the local authority have already failed once to win compensation on the child's behalf. But a further court case will be held at the Court of Appeal tomorrow, with a ruling expected at a later date.
Foetal Alcohol Syndrome (FAS) was diagnosed 252 times in England from 2012 to 2013.
But charities claim there is "continuing uncertainty" over the relationship between drinking and harm to the foetus.
And they say mothers and their babies would not be best served by treating pregnant women with drug or alcohol abuse problems as criminals.
Ann Furedi, chief executive of bpas, and Rebecca Schiller, co-chair of Birthrights, said: "Making one particular form of behaviour during pregnancy into a criminal offence would lay the ground for criminalising a wide range of other behaviours because they may too pose a risk to the health of the baby.
"When we consider that the taking of necessary medication, such as treatment for epilepsy or depression, or the refusal of a caesarean section could be seen to fall into the category of maternal behaviours that may damage the foetus, the trajectory of such an approach is deeply worrying.
"We should take very seriously any legal developments which call into question pregnant women's fundamental right to bodily autonomy and right to make their own decisions.
"Pregnant women deserve support and respect, not the prospect of criminal sanction for behaviour which would not be illegal for anyone else."
Current NHS guidance says women who are pregnant or trying to conceive should avoid alcohol altogether.
But if they choose to drink it recommends they should not have more than one or two units once or twice a week.