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Facts About Fish Consumption and Pregnancy

Fish and shellfish have long been considered one of the healthiest forms of protein. Low in saturated fat and rich in heart-healthy omega-3 fatty acids, they are highly nutritious, but some types of fish and shellfish have become contaminated due to industrial pollution and other causes. Mercury accumulates in the body over time, so even women who aren't planning to conceive right away should pay attention to the amount - and type - of fish they eat.

The first-ever joint recommendations on fish consumption in at-risk populations for methyl mercury poisoning were released in December 2003 by the Food and Drug Administration (FDA) and the Environmental Protection Agency (EPA).

At-risk groups include pregnant women, women who are nursing, women who may become pregnant and young children.

The above groups should follow these precautions:

  • Do not eat shark, swordfish, king mackerel or tilefish, which often contain high levels of mercury.
  • Eat a variety of fish and shellfish and don't eat the same type more than once a week. You can safely eat up to 12 ounces (two to three meals) of other purchased fish and shellfish a week.
  • Check local advisories about the safety of fish caught by family and friends in your local rivers and streams. If no advice is available, you can safely eat up to 6 ounces (one meal) per week of fish caught from local waters, but don't consume any other fish during that week.

What About Other Fish?

New concerns over tuna - one of the most commonly eaten fish - have also grown recently. Canned light tuna has lower levels of mercury than tuna steaks and canned albacore tuna. Experts say that one 6-ounce can per week should be the limit for women of childbearing age and young children.

Farm-raised salmon also pose a concern, as they have been found to contain high levels of cancer-causing PCBs - an environmental pollutant. The PCBs accumulate in the skin and fat of the fish. No recommendations have been released regarding women and farmed salmon, but sticking to wild salmon is the safest approach.

At the fish counter, farm-raised salmon is usually labeled "Atlantic" or "Icelandic," while wild salmon is listed as "Wild" or called "Alaskan." When in doubt, ask your fishmonger about the origin of the fish you buy.