Up to 17% of children could have the symptoms of foetal alcohol spectrum disorder (FASD) because their mothers drank during pregnancy, according to a new study, whose findings were criticised for potentially causing pregnant women to panic and seek an abortion.

Foetal alcohol spectrum disorder is diagnosed from a collection of mental and physical problems in a child, including some distinctive facial features, such as a small head, small eyes and a thin upper lip. It can be associated with learning difficulties and mood problems.

Until now, it was estimated that between 2% and 5% of children in the UK had the disorder as a result of their mother’s alcohol intake while she was pregnant. The NHS says alcohol crosses the placenta to the growing baby, who cannot process it well, resulting in damage to cells in the brain and body.

But the UK has one of the highest reported rates of drinking in pregnancy, at just over 40%, only exceeded by Ireland, Belarus and Denmark, leading some to question the prevalence figure.

The new study, published in the journal Preventive Medicine, was carried out by researchers at Bristol and Cardiff Universities, looking into the records of nearly 13,500 children born in the 1990s whose families had signed up to a major, ongoing study.

They developed a screening tool to analyse the data and assess whether children born to any woman who said she had drunk alcohol during her pregnancy had symptoms consistent with FASD.

They found that 79% of mothers had drunk any alcohol at all when they were pregnant. Between 6% and 17% of the children in the study had symptoms, depending on the exact way in which the researchers did the screening.

Dr Cheryl McQuire, researcher in epidemiology and alcohol-related outcomes at the University of Bristol, who led the research, said this sort of screening “is not the same as a formal diagnosis.

“Nevertheless, the high rates of prenatal alcohol use and FASD-relevant symptoms that we found in our study suggest that FASD is likely to be a significant public health concern in the UK.”

It was important to have better figures, so that children affected could get the help they needed, she said.

However, the British Pregnancy Advisory Service (BPAS) disputed the figures and warned that women who are pregnant could panic and consider abortion if the results were miscommunicated.

“We advise real caution over the interpretation and communication of these findings,” said Clare Murphy, director of external affairs at the charity, which sees over 70,000 women each year for pregnancy counselling and abortion care.

“This study, as the authors themselves acknowledge, does not prove any causal link between pregnancy drinking and the developmental outcomes recorded, and may cause pregnant women and parents needless anxiety.

“Many women have drunk before finding out they are pregnant, and messaging around pregnancy drinking which overstates risk or distorts the available evidence can lead some women to consider ending what would otherwise be a wanted pregnancy, or spend that pregnancy wracked with guilt and anxiety. This does not benefit anyone.”

Campaigners welcomed the findings, however. “These figures should raise alarm bells throughout Westminster and wake up everyone in the NHS and the Department of Health, who for decades have been keeping their heads in the sand about this largely avoidable public health crisis,” said Sandra Butcher, chief executive of the National Organisation for Foetal Alcohol Syndrome-UK.

She and other support groups hail the advice of the chief medical officer, Sally Davies, in 2016, who said it was safest for women who were pregnant or trying to conceive not to drink at all. But they said the government needs a strategy for diagnosing children and supporting the families.

Dr Christopher Steer, of the Royal College of Paediatrics and Child Health, said many cases remained undiagnosed and that screening studies of children are needed. “FASD remains the most common and potentially preventable cause of learning and behavioural difficulties in the world,” he said.

“While we incorporated expert clinical judgment in our algorithm specification and validation process, it was not feasible to conduct individualised assessments of FASD.”