Generally, the health benefits of seafood outweigh the risks associated with methyl mercury, a heavy metal found in varying amounts in much seafood, according to U.S. Department of Agriculture guidelines.

WSJ: Guidelines for Eating Sustainable Seafood

And the finding is particularly pertinent because existing dietary advice to pregnant women, at least in America, is that they should limit their consumption of seafood in order to avoid exposing their fetuses to trace amounts of brain-damaging methyl mercury.

ECONOMIST: Diet and the unborn child