According to a study, expectant mothers should eat fish twice a week to support baby development
- Recent warnings to limit consumption of fish high in mercury have created confusion
- Scientists from the University of Bristol examined data from 4,131 pregnant women
- Babies born to mothers who ate fish had higher IQs and did better in math
Pregnant women should eat at least two servings of fish a week and are no longer advised to avoid certain species, a government-backed study suggests.
Recent warnings to limit consumption of high-mercury fish are creating confusion, prompting mothers-to-be to avoid the food altogether “to be on the safe side,” researchers warn.
This means they are more likely to damage their baby’s development by depriving him of important nutrients like long-chain fatty acids, iodine, vitamin D and selenium.
Researchers from the University of Bristol examined data from 4,131 pregnant women in the UK whose offspring were followed throughout childhood.

Recent warnings to limit consumption of high-mercury fish are creating confusion, prompting mothers-to-be to avoid the food altogether “to be on the safe side,” researchers warn
Mercury levels were measured in maternal blood and umbilical cord tissue.
The analysis found no adverse association between higher maternal mercury levels and cognitive development in babies whose mother ate fish, with experts believing the nutrients in the diet protect against the metal.
In addition, babies born to mothers who ate fish tended to have higher IQs and did better on math and science tests.
The NHS website says pregnant women should eat no more than two servings 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 others.
“This is due to the amounts of mercury and pollutants that some fish can contain. If you eat too much mercury, it can harm your unborn baby.”
The co-author of the study, Dr. Caroline Taylor, writing in the journal NeuroToxicology: “We found that maternal mercury levels during pregnancy are unlikely to adversely affect child development, provided the mother eats fish.
“If she wasn’t eating fish, then there was evidence that her mercury levels could have a harmful effect on the child.”
The study was funded by the UK Medical Research Council and the UK Wellcome Trust.
