hi found this on the mayo clinic it should answer your question. seafood can be a great source of protein and the omega-3 fatty acids in many fish can promote your baby's brain development. however some fish and shellfish contain potentially dangerous levels of mercury. too much mercury could damage your baby's developing nervous system. the bigger and older the fish the more mercury it's likely to contain. the food and drug administration (fda) and the environmental protection agency (epa) encourage pregnant women to avoid: swordfish shark king mackerel tilefish so what's safe? some types of seafood contain little mercury. although concerns have been raised about the level of mercury in any type of canned tuna the fda and epa say pregnant women can safely eat up to 12 ounces (340 grams) a week. similarly the 2010 dietary guidelines for americans recommend 8 to 12 ounces of seafood a week for pregnant women. that's about two average meals of: shrimp crab canned light tuna (limit albacore tuna chunk white tuna and tuna steak to no more than 6 ounces or 170 grams a week) salmon pollock catfish cod tilapia not all researchers agree with these limits however citing a study that noted no negative effects for women who ate more seafood than the fda-approved guidelines. do hope this helps you and your baby to be. good luck
can i eat canned clams while pregnant?