Are mussels safe during pregnancy?

What does the evidence say about mussels during pregnancy?

1. Shellfish should be cooked to a minimum internal temperature of 145°F to lower the risk of foodborne illness in pregnancy, the same benchmark used for fish. 1
2. Fish and shellfish are the main dietary source of methylmercury, and the FDA and EPA recommend pregnant women eat up to 12 ounces a week, split between 'Best Choices' and 'Good Choices' options, to limit exposure while still getting the nutritional benefits of seafood. 2
3. Filter-feeding shellfish can concentrate Vibrio bacteria from the surrounding water, and nearly all Vibrio vulnificus and Vibrio parahaemolyticus infections in the US come from eating raw or undercooked bivalves, though the bacteria themselves are heat-sensitive and killed by thorough cooking. 3
4. In rare cases, Vibrio vulnificus infection can progress to a serious bloodstream infection within hours to a couple of days after eating a contaminated raw or undercooked oyster or other bivalve, which is why standard food-safety guidance is to skip raw shellfish preparations during pregnancy and choose fully cooked options instead. 3
5. Norovirus is more heat-tolerant than many other pathogens, and research on oysters, a bivalve shellfish similar to mussels, found that simply cooking until the shell pops open did not reliably inactivate the virus: cooking for about 10 minutes at 85°C (185°F) was identified as more effective, which is why cooking mussels at a full boil or steam for the recommended time, not just until shells crack, matters. 4

Is mussels safe in each trimester?

• First trimester. Mercury and infection risk from shellfish are relevant across all three trimesters, so the same rule applies now: fully cooked mussels are fine, raw or undercooked ones are not.
• Second trimester. As your protein needs rise, fully cooked mussels are a lean source of iron and B12 alongside other seafood. Keep tracking your total weekly seafood intake toward the 12-ounce guideline.
• Third trimester. Dehydration from vomiting or diarrhea is worth taking seriously this trimester, so call your provider if a foodborne illness has you unable to keep fluids down, on top of sticking with fully cooked mussels.