Clam chowder is generally safe to eat during pregnancy, as long as the clams are fully cooked and the soup is served hot. Clams fall into the FDA’s “Best Choices” category for mercury, making them one of the lowest-risk seafood options available. The main concerns are undercooking and how the chowder is prepared, not the clams themselves.
Why Clams Are a Low-Mercury Choice
The FDA ranks all commercial fish and shellfish into three tiers based on mercury content: Best Choices, Good Choices, and Choices to Avoid. Clams land in the Best Choices tier, meaning they contain very little mercury. Pregnant and breastfeeding women can safely eat two to three servings per week from this category, with one serving defined as about 4 ounces (roughly the size of your palm).
A typical bowl of clam chowder contains well under 4 ounces of actual clam meat, so even eating it a few times a week would keep you comfortably within safe limits.
Cooking Temperatures Matter Most
The real risk with any shellfish during pregnancy is undercooking. Raw or undercooked clams can harbor bacteria like Vibrio and parasites like Toxoplasma gondii. Clams are filter feeders, meaning they constantly pull water through their bodies to trap food. That same process can concentrate pathogens from the surrounding water in their tissues.
The FDA advises cooking clams until their shells open, then discarding any that stay shut. Shucked clams (the kind used in most chowder recipes) are fully cooked when they turn opaque, milky white, and firm. Toxoplasma oocysts, which have been detected in small percentages of clam samples in studies from Canada and Tunisia, are destroyed when the internal temperature reaches at least 64°C (about 147°F). A properly simmered chowder easily exceeds that threshold.
If your chowder is bubbling on the stove or arrives steaming at a restaurant, the clams inside have reached a safe temperature.
Canned Clam Chowder vs. Restaurant or Homemade
Canned, shelf-stable clam chowder is one of the safest options. The commercial canning process uses high heat and pressure that kills virtually all bacteria, including Listeria, which is a particular concern during pregnancy because it can cross the placenta. Once sealed, the product stays sterile until you open it. Campbell’s, Progresso, and store-brand varieties all fall into this category.
Restaurant or deli chowder is also fine as long as it’s served hot, not lukewarm. Soups that sit at improper temperatures for extended periods can allow bacteria to multiply. If you’re ordering from a restaurant, a freshly ladled bowl from a heated pot is your safest bet. Avoid chowder from a buffet line that’s been sitting out for an unknown amount of time.
Homemade chowder follows the same rules. Bring it to a full simmer, make sure the clams are cooked through, and refrigerate leftovers within two hours. When reheating, bring it back to a rolling temperature rather than just warming it.
Nutritional Benefits for Pregnancy
Beyond being safe, clams are one of the most nutrient-dense shellfish you can eat. They’re an excellent source of iron, which many pregnant women run low on, especially in the second and third trimesters. A 3-ounce serving of clams provides more iron than a similar serving of beef. They’re also rich in vitamin B12, zinc, and protein, all of which support fetal development.
Clam chowder made with milk or cream adds calcium to the mix. The overall nutritional profile makes it a surprisingly solid meal choice during pregnancy, not just a safe one.
Types of Chowder to Watch Out For
Not all chowder preparations carry the same level of risk. A few situations call for extra attention:
- Raw bar “chowders”: Some seafood restaurants serve chilled or raw clam preparations that they loosely call chowder. If the clams aren’t cooked, skip it.
- Chowder with smoked clams or seafood: Refrigerated smoked seafood can carry Listeria unless it’s been heated in a cooked dish. If smoked clams are added to a hot, simmered chowder, the risk is neutralized. Cold smoked seafood on its own is best avoided.
- Leftover chowder reheated insufficiently: Dairy-based soups are a hospitable environment for bacterial growth. Reheat leftovers to a full simmer, not just until warm.
Standard New England clam chowder (cream-based) and Manhattan clam chowder (tomato-based) are both safe choices when cooked properly. The broth base doesn’t change the safety equation, only whether the clams reached the right temperature.