Fish and Seafood During Pregnancy

Fish is one of the most confusing foods in pregnancy. It is simultaneously the single best dietary source of the omega-3 DHA your baby's brain needs, and the food most associated with mercury warnings.

Both things are true, and the resolution is species selection. The FDA and EPA actively recommend that pregnant women eat 8 to 12 ounces of low-mercury fish per week, rather than avoiding fish.

Avoiding seafood entirely is its own risk. Research links inadequate maternal DHA to poorer neurodevelopmental outcomes, so the goal is choosing the right fish, not skipping it.

This guide covers every common fish and shellfish, which are considered safe, which to limit, and which to avoid.

🐟 The FDA Categories: How Fish Safety Actually Works

The FDA and EPA sort fish into three tiers based on average mercury content. The chart injected below lists the common species by category.

Best Choice fish are low enough in mercury to eat 2 to 3 servings weekly, totaling 8 to 12 ounces. This is where most everyday seafood sits, including shrimp, salmon, cod, tilapia, catfish, sardines, crab, and lobster.

Good Choice fish carry moderate mercury and are limited to 1 serving per week. Albacore tuna and Spanish mackerel are the common examples.

Avoid fish are the four highest-mercury species: shark, swordfish, king mackerel, and tilefish. These accumulate enough mercury that no amount is recommended during pregnancy.

🔑 Key Takeaway: The FDA recommends 8 to 12 oz (2 to 3 servings) of low-mercury fish per week during pregnancy. Mercury accumulates up the food chain, so small, short-lived fish are low in mercury while large predators are high. Choosing correctly matters more than eating less.

☠️ Why Mercury Matters, and Why Most Fish Is Fine

Mercury bioaccumulates. Small fish absorb trace amounts, larger fish eat many small fish and concentrate it, and top predators concentrate it further.

This is why a 400-pound swordfish carries roughly 70 times the mercury of a shrimp. Position in the food chain, not "fish" as a category, determines the risk.

Methylmercury crosses the placenta and can affect fetal neurological development, which is the reason for the guidance. But the dose and the source are what matter.

The practical upshot is reassuring. Bottom-dwelling and small forage species, which cover most of what people actually eat, sit in the lowest-mercury tier.

It also helps to know what the weekly limits are actually protecting against. The guidance is built around cumulative exposure over the whole pregnancy, not around any single meal being dangerous.

That means an occasional serving slightly over the limit is not a crisis. If you ate albacore twice in one week, the sensible response is to choose lower-mercury fish the following week, not to worry.

The bigger and more common mistake runs the other direction. Many women cut fish out entirely on hearing "mercury," and in doing so lose the DHA that the guidance was never trying to take away.

📌 Note: The FDA revised its advice specifically because avoidance had become the default. The current framing is deliberately worded as advice about eating fish, not avoiding it, because the evidence favors eating low-mercury fish over eating none.

🦐 Shrimp and Prawns

Shrimp is the most-consumed seafood in the US and among the safest in pregnancy. At roughly 0.01 ppm mercury, it is in the FDA's lowest-mercury tier.

Prawns are, for safety purposes, simply large shrimp. The same rules apply: same mercury profile, same cooking requirement, same weekly allowance.

Cook both to 145°F. Properly cooked shrimp turns pink and opaque and curls into a C shape; a tight O shape usually means it is overcooked.

Avoid raw preparations such as ceviche and shrimp sashimi. The concern with raw shellfish is bacterial and viral contamination rather than mercury.

Nutritionally, a 3 oz serving delivers about 20 g of protein with very little fat, plus meaningful iodine and selenium. Iodine matters in pregnancy for fetal thyroid and brain development.

Shrimp does carry more cholesterol than most seafood, which occasionally worries people. Dietary cholesterol has a modest effect on blood cholesterol for most people, and shrimp is not considered a concern in a normal pregnancy diet.

The more practical shrimp question is shellfish allergy. If you are allergic, pregnancy is not the time to test it, and there is no evidence that eating or avoiding shellfish while pregnant changes your baby's allergy risk.

Buying and storing matters too. Shrimp spoils quickly, so buy it fresh or frozen from a reliable source, keep it cold, and cook it within a day or two of thawing.

🦀 Crab and Lobster

Both are considered safe when fully cooked, and both sit in the Best Choice tier. This surprises people who assume shellfish means high mercury.

Lobster averages about 0.10 ppm mercury, lower than tuna and far below the avoid-list species. It is a bottom-dwelling omnivore, which keeps it low on the food chain.

Crab is lower still. King crab (0.027 ppm), snow crab (0.040), blue crab and Dungeness (0.065) are all Best Choice.

Cook both to 145°F. Lobster shell turns bright red and the meat becomes opaque; crab meat should be opaque throughout with no translucent centers.

Imitation crab, or surimi, is also considered safe. It is made from fully cooked processed white fish, usually pollock, and is pasteurized during manufacturing.

The one caution with imitation crab is that it is often used in sushi rolls. The imitation crab itself is cooked and fine, but other ingredients in the roll may not be.

Crab is notably rich in zinc (about 6.5 mg per 3 oz) and B12 (about 9 mcg), both of which matter for immune function and neurological development.

🐠 Everyday White Fish: Cod, Tilapia, Catfish

These three are the workhorses of low-mercury eating, and all sit firmly in Best Choice.

Tilapia is among the lowest at 0.013 ppm, delivering about 21 g of protein per 3 oz. Catfish is similar at 0.024 ppm with about 15 g of protein. Cod is comparably low.

All should be cooked to 145°F until the flesh flakes easily and is opaque. None should be eaten raw.

The one trade-off is DHA. These lean white fish contain far less omega-3 than fatty fish, so they are excellent protein but should be balanced with higher-DHA options.

Farm-raised and wild-caught are both considered safe for these species. The mercury difference between them is not meaningful at these levels.

These fish are also the easiest entry point if seafood is not something you normally eat. They are mild, inexpensive, widely available, and forgiving to cook, which makes hitting the weekly 8 to 12 oz target realistic rather than aspirational.

Pollock and haddock belong in the same group and follow the same rules. Fish sticks and breaded fish fillets made from these species are fully cooked products and are considered safe when heated per the package.

One caveat is preparation rather than the fish itself. Deep-fried fish and heavy batter add little nutritionally, so baking, pan-searing, or grilling keeps the benefit without the extras.

🐟 The DHA Powerhouses: Salmon and Sardines

If DHA is the reason to eat fish in pregnancy, these two are the best answers.

Sardines are arguably the most nutrient-dense fish available. A 3 oz serving of canned sardines provides roughly 740 mg of DHA, which is two to three times the daily minimum, along with 22 g of protein.

Eaten with the bones, sardines also deliver about 325 mg of calcium, roughly a third of the pregnancy daily need, plus vitamin D and about 8.9 mcg of B12. Mercury is very low at 0.013 ppm.

Canned sardines are pre-cooked during canning and are safe to eat straight from the tin. No further cooking is required.

Salmon is the other standout, combining high DHA with low mercury and wide availability. Our salmon during pregnancy guide covers it in depth, including farmed versus wild.

💡 Tip: If you eat only lean white fish, you may be meeting protein needs while missing DHA. A practical pattern is to make at least one of your two to three weekly servings a fatty fish like salmon or sardines, and fill the rest with whatever low-mercury fish you enjoy.

⚠️ Mackerel: The Species Trap

Mackerel is the clearest example of why species matters more than the name on the menu.

Atlantic mackerel is Best Choice at 0.050 ppm and provides over 1,000 mg of DHA per serving. It is one of the better fish you can eat in pregnancy.

King mackerel is on the FDA avoid list at 0.730 ppm. It is one of only four fish the FDA says to skip entirely.

Spanish mackerel sits in between at 0.182 ppm, a Good Choice limited to one serving per week.

⚠️ Warning: "Mackerel" on a menu or at a fish counter is ambiguous, and the difference between Atlantic and King is the difference between a recommended fish and an avoid-list fish. Always ask which species it is. If nobody can tell you, skip it.

🔥 Smoked Salmon: Hot vs Cold

This distinction catches many people, because both products are labeled smoked salmon but only one is cooked.

Hot-smoked salmon reaches 145°F or above during smoking, which cooks it through. It is considered safe, and its texture is flaky and opaque like cooked salmon.

Cold-smoked salmon, sold as lox or nova, is smoked at temperatures too low to cook the fish. It stays silky, translucent, and sliceable, essentially raw salmon with smoke flavor.

Cold-smoked salmon should be avoided during pregnancy unless heated to 165°F first, because the low smoking temperature does not kill Listeria. Baked into a hot dish, it is fine.

The texture test is the most practical rule. If it looks raw, treat it as raw.

Canned smoked salmon is sterilized during canning and is considered safe as-is.

🦪 Oysters and Raw Shellfish

Raw oysters should be avoided during pregnancy. The concern here is not mercury but Vibrio bacteria and norovirus, which raw shellfish can carry.

Cooked oysters are a different matter and are considered safe when fully cooked. Cooking eliminates the pathogens of concern.

The same logic applies to raw clams, raw mussels, and any raw shellfish preparation. Cooked versions are considered safe; raw ones are not.

For raw fish generally, including sushi and sashimi, see our sushi during pregnancy guide.

🍣 What About Tuna?

Tuna deserves its own treatment because the answer depends entirely on the type. Canned light tuna is low mercury and Best Choice, while albacore and bigeye run much higher.

Our tuna during pregnancy guide breaks down each variety with weekly limits.

🌡️ Cooking Seafood Safely

Nearly every fish and shellfish question in pregnancy resolves to two variables: mercury and cooking. The steps below cover the cooking side.

The universal target is 145°F internal temperature for fish and shellfish. At that point fish flakes easily and is opaque, shrimp is pink and C-shaped, and crab and lobster meat is opaque with a bright red shell.

Canned and pre-cooked seafood, including canned sardines, canned salmon, canned tuna, and imitation crab, is already cooked during processing and needs no further heating.

Cross-contamination is the other half of safe handling. Raw fish juices can carry bacteria, so keep raw seafood separate from ready-to-eat foods, use a separate cutting board, and wash hands and surfaces afterward.

Leftovers deserve a little more care than usual during pregnancy. Refrigerate cooked seafood within two hours, eat it within a day or two, and reheat it until steaming hot rather than eating it cold from the fridge.

A digital thermometer removes most of the guesswork. Visual cues work well for shrimp and lobster, but for thicker fillets the temperature reading is more reliable than appearance alone.

🎯 Bottom Line: Eat 8 to 12 oz of low-mercury fish weekly rather than avoiding seafood. Stick to Best Choice species, cook everything to 145°F, skip raw preparations and cold-smoked fish, avoid the four high-mercury species, and make sure at least one weekly serving is a fatty fish for DHA.

❓ Frequently Asked Questions

How much fish can I eat during pregnancy?

The FDA and EPA recommend 8 to 12 ounces per week of low-mercury fish, which is about 2 to 3 servings. This is a recommendation to eat fish, not merely a ceiling, because the DHA benefits for fetal brain development are well established.

Which fish should I avoid completely during pregnancy?

Four species: shark, swordfish, king mackerel, and tilefish from the Gulf of Mexico. These accumulate the highest mercury levels. Bigeye tuna is also on the avoid list in the FDA's advice.

Is shrimp safe during pregnancy?

Yes, when cooked to 145°F. Shrimp is among the lowest-mercury seafood at roughly 0.01 ppm and is an FDA Best Choice. Avoid raw shrimp preparations such as ceviche.

Can I eat crab and lobster while pregnant?

Yes, both are considered safe when fully cooked to 145°F. Both are FDA Best Choice with low mercury, lobster around 0.10 ppm and crab even lower. Imitation crab is also considered safe since it is pre-cooked.

Is canned tuna safe during pregnancy?

Canned light tuna is low mercury and considered safe within the weekly allowance. Albacore (white) tuna is higher and limited to one serving per week. See our tuna guide for the full breakdown by type.

Are sardines safe during pregnancy?

Yes, and they are among the most nutritious choices available. Very low mercury at 0.013 ppm, with about 740 mg DHA and 325 mg calcium per serving when eaten with bones. Canned sardines are pre-cooked and safe from the tin.

Can I eat smoked salmon when pregnant?

Hot-smoked salmon is considered safe because it reaches 145°F during smoking. Cold-smoked salmon and lox should be avoided unless heated to 165°F, since cold smoking does not reach temperatures that kill Listeria.

Is Atlantic mackerel the same as king mackerel?

No, and the difference matters. Atlantic mackerel is a low-mercury Best Choice, while king mackerel is on the FDA avoid list at 0.730 ppm. Always confirm the species before eating mackerel.

Can I eat oysters while pregnant?

Cooked oysters are considered safe. Raw oysters should be avoided because of Vibrio bacteria and norovirus risk, which cooking eliminates. The same applies to raw clams and mussels.

Is farmed fish as safe as wild-caught during pregnancy?

For the low-mercury species covered here, both are considered safe and the mercury difference is not meaningful. Choose based on preference, cost, and availability.

Why does DHA matter so much in pregnancy?

DHA is a structural fat that the fetal brain and retina need for development, and fish is the richest dietary source. This is why the FDA frames its advice as eat fish, choosing wisely, rather than avoid fish.

Sources

1. FDA/EPA. Advice About Eating Fish: For Those Who Might Become or Are Pregnant or Breastfeeding. U.S. Food and Drug Administration, 2021, updated 2024.
2. FDA. Mercury Levels in Commercial Fish and Shellfish. U.S. Food and Drug Administration, 2023.
3. ACOG. Nutrition During Pregnancy. American College of Obstetricians and Gynecologists, 2023.
4. FDA. Food Safety for Pregnant Women. U.S. Food and Drug Administration, 2023.
5. CDC. Listeria Infection (Listeriosis): Prevention. Centers for Disease Control and Prevention, 2023.

This guide is for informational purposes and does not replace advice from your healthcare provider. Mercury guidance and fish advisories can vary by region and local waterway, so check local advisories for locally caught fish.

Related guides:

• Salmon During Pregnancy
• Tuna During Pregnancy
• Sushi and Raw Fish During Pregnancy
• Pregnancy Safe Food Checker