London, UK (BBN)-Pregnant women should avoid alcohol altogether, the chief medical officer for Wales has warned.
Dr Ruth Hussey was speaking ahead of a special conference on the issue hosted by Alcohol Concern Cymru in Cardiff, reports BBC.
Latest figures estimate 39 per cent of mothers-to-be in Wales drink alcohol although mostly only in low amounts.
Bur Dr Hussey said in practice it was easy to underestimate the quantity in a glass and difficult to measure units of alcohol accurately.
The proportion of pregnant women who say they drink some alcohol in Wales has been falling, according to the last survey of infant feeding by the UK's four health departments.
The National Institute for Health and Clinical Excellence (NICE) advises that pregnant women who choose to drink alcohol should not drink more than one to two units - equivalent to a small to medium glass of wine - once or twice a week.
NICE says the first three months of a pregnancy are particularly important.
Dr Hussey said: "The advice is to avoid alcohol altogether when pregnant, including when trying to conceive - so when trying for a baby or pregnant, keep it simple - no alcohol, no risk."
The Welsh government's Change4Life Wales website has received more clicks on its alcohol and pregnancy pages in the last year than any other section.
It is the theme of the alcohol campaign group's conference in Cardiff, which also includes contributions from Cardiff Central AM Jenny Rathbone and academics and health experts.
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