How your diet affects your chances of having children

Unhealthy eating ­triggers a sharp decline in fertility levels, scientists warn. Scientists found fertilisation rates were lowest in couples where men had diets highest in trans fats - found in cakes, biscuits and takeaway food

Slender people are just as unlikely to have children as the obese if they have a diet containing a lot of fat.

Three major new studies on diet will be presented today at the world’s biggest fertility conference, the annual American Society for Reproductive Medicine meeting, in Baltimore.

They suggest eating high levels of fat can dramatically slash the chances of couples getting pregnant, damage ovaries and produce poor quality embryos.

Researchers at Harvard School of Public Health studied the impact on fertility rates of high trans fat intake in men trying to conceive through IVF.

They found fertilisation rates were lowest in couples where men had diets highest in trans fats - found in cakes, biscuits and takeaway food.

Men with the best diets had 83% chance of getting their partner pregnant, compared with 47% for those with the worst diets.

Experts at the University of Colorado, Denver, found mice fed a high fat diet had damaged ovaries and produced poor fertility rates - even if they were not fat.

And a third study by the Universities of North and South Carolina found women with low levels of viable embryos and fertilisation rates had high levels of elaidic acid in their blood streams - suggesting they had eaten a lot of fried food.

Speaking at the annual ASRM meeting in Baltimore, Dr Richard Kennedy, president elect of the International Federation of Fertility Societies (IFFS), warned: “Obesity is a major public health issue and there is no doubt it is related to certain aspects of fertility, specifically egg production and quality.”

Dr Edgar Mocanu, another member of the executive committee of the IFFS, blamed poor diets for a worrying fall in fertility levels in recent decades in Western countries including the UK.

He warned: “I think it is a problem and could be behind declining sperm rates.”

Top fertility expert Prof Charles Kingsland, of Liverpool Women’s Hospital, also warned that diet was crucial for pregnancy.

He said: “It’s well known that a good balanced diet is good for fertility and unhealthy foods can be harmful particularly if your fertility is poor to start with.”

Dr Owen Davis, president elect of the American Society for Reproductive Medicine, added: “These kind of studies allow us to better counsel our patients on their nutritional needs while attempting to become pregnant.”