Muka · Pregnancy guide
Is It Safe to Eat Shellfish During Pregnancy?
Updated June 2026 · based on NHS and official food-safety guidance
The NHS, FDA and ACOG all agree that cooked shellfish such as prawns, mussels, crab, scallops and clams is safe and a good source of protein and omega-3. Raw and undercooked shellfish can carry bacteria, viruses and toxins (Vibrio, Listeria, norovirus) that cause food poisoning, which is riskier in pregnancy. Cook shellfish until steaming hot throughout (the FDA advises an internal temperature of 145°F / 63°C, and until the shells of clams, mussels and oysters open).
Shellfish is one of the most common pregnancy food worries, partly because so much of it is served raw or barely cooked. The good news from official guidance is reassuringly simple: cooking is the dividing line. Thoroughly cooked prawns, mussels, crab, scallops and clams are safe and nutritious, while raw oysters and other uncooked shellfish are the ones to avoid. The UK's NHS and the US FDA, EPA and ACOG line up closely here, with only minor differences on portion sizes for mercury. This guide breaks down what is safe, what to avoid, and how to check your shellfish is cooked properly. For a specific product, the Muka app gives you a verdict in 3 seconds by barcode scan or photo.
Shellfish in pregnancy: what is safe and what to avoid
| Shellfish | Verdict | Why |
|---|---|---|
| Thoroughly cooked prawns or shrimp | Safe | Prawns turn from grey to pinky-red when cooked through. Hot or cold pre-cooked prawns are fine, and shrimp is a low-mercury FDA Best Choice. |
| Cooked mussels, clams and scallops | Safe | Safe once cooked until steaming hot. For mussels and clams, cook until the shells open and discard any that stay shut. |
| Cooked crab | Safe | Low-mercury FDA Best Choice and NHS-approved when fully cooked. Eat in normal portions; brown crab meat is high in cadmium, so limit it. |
| Cooked lobster | Safe | Lobster (American and spiny) is a low-mercury FDA Best Choice and NHS-approved when fully cooked. Enjoy it cooked until steaming hot. |
| Raw oysters | Avoid | Filter-feeders that can carry Vibrio, norovirus and other pathogens. NHS, FDA and ACOG all advise avoiding raw oysters and other raw shellfish. |
| Undercooked shellfish in sushi, ceviche or marinated dishes | Avoid | Lime juice or marinades do not kill bacteria. Only choose shellfish that has been cooked until hot, not raw or lightly cured. |
Not sure about a specific product?
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Download Muka on the App StoreFrequently asked questions
Can I eat cooked prawns when pregnant?
Yes. Thoroughly cooked prawns are safe during pregnancy, whether served hot or cold. Cooked prawns turn pinky-red, which is your visual cue they are done. Cold pre-cooked prawns, like those in a sandwich or salad, are fine as long as they were properly cooked and have been kept chilled.
Why are raw oysters not safe in pregnancy?
Oysters are filter-feeders that concentrate bacteria, viruses and toxins from the water, including Vibrio, Listeria and norovirus. In pregnancy your immune system is more vulnerable, and food poisoning can be serious for you and your baby. Thorough cooking kills these pathogens, so cooked oysters are fine but raw oysters are not.
I ate raw shellfish before I knew I was pregnant. Should I worry?
Try not to panic. A single exposure is low-risk, and most people have no problems at all. Watch for food-poisoning symptoms like vomiting, diarrhoea or fever over the next few days. If you feel unwell or are concerned, contact your midwife, GP or doctor for reassurance and advice.
How much shellfish can I eat each week in pregnancy?
The FDA and EPA advise 8 to 12 ounces (about 2 to 3 servings) of low-mercury seafood per week, and shrimp, crab, lobster, clams, oysters and scallops are all low-mercury Best Choices. The NHS sets no specific shellfish limit, focusing instead on making sure it is fully cooked.
Are mussels safe to eat during pregnancy?
Yes, cooked mussels are safe. Cook them until the shells open and the flesh is piping hot, and throw away any mussels that stay closed after cooking. Avoid raw or barely steamed mussels. Mussels are low in mercury and a good source of protein, iron and omega-3 for pregnancy.
Can I eat shellfish if I have it at a restaurant?
Yes, if it is fully cooked. Order shellfish dishes served hot, such as cooked prawns, mussels or crab, and avoid raw bars, oyster platters, ceviche and sushi made with raw shellfish. If you are unsure how something is prepared, ask the staff or choose a thoroughly cooked option instead.
Sources
- NHS — Foods to avoid in pregnancy: nhs.uk
See also: how Muka works, the pregnancy food scanner that answers “can I eat this while pregnant?”.