The following questions-and-answers on safe fish consumption before conception and during pregnancy come from Eating for Pregnancy: The Essential Nutrition Guide and Cookbook for Today’s Mothers-to-Be, winner of the 2009 Mom’s Choice Gold Award! As Diane Snyder, MD, OB/GYN said: “As an obstetrician this is a welcome resource for our patients. We often wish we had more time during prenatal visits to review healthy eating and recommendations for adequate nutrition. This book is a welcome addition.” This information is from a text box on page 320.
What is mercury and methylmercury?
Mercury occurs naturally in the environment, and it can also be released into the air through industrial pollution. Mercury falls from the sky, accumulating in streams and oceans, where it turns into methylmercury in the water. Fish absorb methylmercury as they feed. High amounts of methylmercury in certain types of fish can potentially be harmful to the neurological development of an unborn baby and young child.
Is there methylmercury in all fish and shellfish?
Nearly all fish and shellfish contain traces of methylmercury. Large fish (swordfish, shark, king mackerel, and tilefish) with long lifespans have the highest levels of methylmercury, mainly because they’ve had more time to accumulate it. These fish pose the greatest risk. Other types of fish should be eaten in amounts recommended by the FDA and EPA.
What about fish sticks and fast food sandwiches?
Fish sticks and fast-food sandwiches are usually made from fish that are low in mercury, so they are safe to eat.
What about tuna steaks?
Because tuna steak generally contain higher levels of mercury than canned light tuna, you may eat up to 6 ounces (one average meal) of tuna steak per week.
What if I eat more than the recommended amount of fish and shellfish in a week?
One week’s consumption of fish does not change the level of methylmercury in your body much at all.
I’m trying to conceive. Should I be concerned about methylmercury?
If you regularly eat fish high in methylmercury, it can accumulate in your bloodstream over time. Methylmercury is excreted from the body naturally, but it may take over a year for high levels to drop significantly. Therefore, it may be present in a woman before she becomes pregnant. For this reason, women who are trying to conceive should also try to avoid eating high-mercury fish, but they certainly should eat other fish.
Source: EPA, U.S. Environmental Protection Agency [Internet]. Fish Advisories, Consumption Advice, Joint Federal Advisory for Mercury in Fish, “What You Need to Know about Mercury in Fish and Shellfish, 2004 EPA and FDA Advice for Women Who Might Become Pregnant, Women Who Are Pregnant, Nursing Mothers, and Young Children.” [last updated August 14, 2008; cited September 2008]. Available from www.epa.gov/waterscience/fishadvice/html.
More about Fish, Methylmercury, Omega-3, Safe Fish
If you want to eat more fish but are scared of choking on the bones, fear no more. This trick should help you get rid of pin bones from salmon and other fish filets. Drape the filet, flesh-side up, over an inverted medium-size or large bowl, depending on the size of the filet. To remove the bones, use fish-bone tweezers, small pliers, or your hands and a paper towel for gripping and pulling. The pin bones should protrude, but run your fingers down the center of the filet to make sure you remove all of them.
There is no definitive answer to this question because so many variables need to be considered, including the diet of the fish. In general, farmed-fish that are fed fishmeal and fish oil tend to have more omega-3s than those fed a grain-based diet heavy on vegetable oils (a common choice because it is cheaper). Wild fish eat a naturally varied diet, including krill and other sea creatures, plus algae. All “Atlantic salmon” is farm-raised, a reality stemming from the fact that wild sources have been depleted from the ocean. All “Alaskan salmon” is wild, and much of it is canned. The “Pacific species,” including coho (silver) and Chinook (king) can be wild or farmed. Bottom line: On the whole, it is probably safe to say that wild-caught and farm-raised salmon have approximately the same amount of omega-3s. Read more 
