Young Britons are clueless when it comes to the facts of life, a survey released yesterday shows.

More than 20 per cent of 18- to 25-year-olds questioned thought a pregnancy lasted a year, 10 per cent believed eating red meat influenced the sex of a baby and half expected a baby to walk and talk within its first year.

The poll also revealed that 20 per cent of the childless respondents thought the umbilical cord was a musical note and 27 per cent admitted they would consider genetic engineering if it meant a better-looking baby.

The vast majority (70 per cent) were in the dark when it came to the true cost of raising a baby.

A third of the respondents believed that £1,000 would be adequate to cover equipment, food, clothes and toys for a baby’s first year when the latest studies suggest it is about nine times higher.

Relationship expert Tracey Cox said: “The study would suggest that young British adults have a lot of faith in the speed of evolution, with babies walking and talking in their first year.”