Eat fish twice a week, mums-to-be told

PREGNANT women should eat at least two portions of fish a week and no longer be advised to avoid certain species, a government-backed study suggests.

Current warnings to limit the intake of fish high in mercury cause confusion and lead mums-to-be to shun the food entirely ‘to be on the safe side’, researchers warn.

This means they are more likely to harm their baby’s development by depriving them of key nutrients, such as long-chain fatty acids, iodine, vitamin D and selenium.

Scientists from the University of Bristol examined data on 4,131 pregnant women in the UK whose offspring were followed throughout childhood.

Mercury levels were measured in maternal blood and umbilical cord tissue. Analysis found no adverse link between higher maternal mercury levels and cognitive development in babies whose mother ate fish, with experts believing the nutrients in the food protect against the metal.

Furthermore, babies born to mums who ate fish typically had higher IQs and performed better in maths and science tests.

The NHS website says pregnant women should eat no more than two portions of oily fish and no more than two tuna steaks a week. It also says to ‘avoid’ swordfish and raw shellfish, adding: ‘Pregnant and breastfeeding women should avoid some types of fish and limit the amount they eat of some others. This is because of the levels of mercury and pollutants that some fish can contain. If you eat too much mercury, it can be harmful to your unborn baby.’

Writing in the journal NeuroToxicology, study co-author Dr Caroline Taylor said: ‘We found that the mother’s mercury level during pregnancy is likely to have no adverse effect on the development of the child, provided that the mother eats fish.

‘If she did not eat fish, then there was some evidence her mercury level could have a harmful effect on the child.’ The study was funded by the UK Medical Research Council and the UK Wellcome Trust.