It's the first piece of information you're given at the doctor's office for a prenatal checkup: The Dos and Don'ts list of what to eat and what not to eat while pregnant. And it's about to get an update.

In the past, pregnant women have been given advice about the maximum amount of fish they could eat while pregnant. But now, health experts at the Food and Drug Administration and the Environmental Protection Agency have updated that advice to also include a minimum amount of fish that pregnant women should eat, in the hopes of encouraging women to eat more low-mercury seafood during pregnancy.

“For years many women have limited or avoided eating fish during pregnancy or feeding fish to their young children,” said Stephen Ostroff, M.D., the FDA’s acting chief scientist. “But emerging science now tells us that limiting or avoiding fish during pregnancy and early childhood can mean missing out on important nutrients that can have a positive impact on growth and development as well as on general health.”

A recent FDA survey of 1,000 pregnant women in the U.S. found that 21 percent ate no fish at all over the previous four weeks. Of those who did consume some fish, 50 percent ate fewer than 2 ounces a week, and 75 percent ate fewer than 4 ounces a week.

The new update to the rules proposed by the FDA and EPA recommends that pregnant women eat at least 8 ounces and up to 12 ounces (2-3 servings) per week of a variety of fish that are lower in mercury to support fetal growth and development.

Which fish are low in mercury? Good choices include shrimp, pollock, salmon, canned light tuna, tilapia, catfish and cod. High mercury-containing fish that pregnant women should avoid are tilefish from the Gulf of Mexico, shark, swordfish and king mackerel. The updated advice also recommends limiting consumption of white (albacore) tuna to 6 ounces a week.

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