Pregnant women often wonder if oysters are safe to eat during pregnancy as they’re frequently eaten raw. The risks of food poisoning from oysters are well known, even for those who aren’t pregnant.
As an oyster lover, but a cautious one, I put together this in-depth guide to oysters during pregnancy, including all the popular ways they are served and cooked, and whether they’re safe or not.
Are Oysters Shellfish?
When you’re pregnant you’ll probably already know that you should avoid raw or undercooked seafood or shellfish, but are oysters shellfish? Oysters are bivalve molluscs, like mussels and clams, but for the purposes of pregnancy safety, treat them as shellfish.
Can Pregnant Women Eat Raw Oysters?
Since the most common way of serving oysters is freshly shucked and raw, I’ll deal with raw oysters here first.
Pregnant women should avoid raw oysters. This is because they can contain bacteria, toxins or other pathogens that can lead to serious food poisoning (source: NHS).
One of the more well-known pathogens that oysters may contain is Vibrio vulnificus, which causes a disease called vibriosis. Vibriosis has the potential to make anyone seriously ill, not just pregnant women.
According to the Center for Disease Control and Prevention, around 80,000 people get vibriosis every year in the US from eating raw seafood (particularly oysters).
Approximately 100 of those people die, however, deaths tend to occur in people who are already immunocompromised or have other underlying health conditions (source: CDC).
During pregnancy, women are not “immunocompromised” in the same way described by the CDC, however, there are still significant changes to the immune system during pregnancy, and it’s wise to avoid any bacterial or viral diseases (source: American Journal of Reproduction Immunology).
The only way to destroy vibrio bacteria is by cooking. No other method works – it’s a myth that toppings like vinegar, hot sauce, lemon juice or alcohol will kill pathogens. If the oyster isn’t fully cooked, it’s still a risk, and should be avoided during pregnancy.
Help – I ate Raw Oysters and I’m Pregnant. What Now?
Having read the above, you might now be worried that you accidentally ate raw oysters while pregnant and are now concerned. The key thing is not to panic – the odds of the oyster being infected or otherwise unsafe are still very low.
Many types of shellfish poisoning become apparent quite quickly – from 4-48 hours (source: WebMD). If it’s been longer than this, then it’s unlikely that you’ll be affected. Going forward, avoid raw oysters and seafood for the duration of your pregnancy.
If you have any symptoms that are out of the ordinary for you, such as vomiting, diarrhea, gastrointestinal discomfort or similar, contact your healthcare provider straight away and let them know you ate raw oysters. It could be that nausea or feeling sick may simply be morning sickness, but it’s better to be on the safe side.
Can I Eat Cooked Oysters During Pregnancy?
Pregnant women can eat oysters if they are fully cooked, because the heat will destroy most bacteria or toxins (source: CDC)
So what does ‘fully cooked’ mean?
Below, I’ve listed the most common ‘cooked’ oyster dishes and methods, including tips for if you’re cooking oysters yourself at home during your pregnancy:
Fried Oysters – These are usually fully cooked (and therefore safe in pregnancy) as they’re breaded or battered, and then deep-fried. If you want to be super safe, cut the biggest one in half and check if its steaming hot in the center.
Bear in mind that this does add quite a bit of calories and fat, so it’s best to eat deep-fried foods in moderation when you’re pregnant.
Steamed Oysters – are safe to eat when pregnant if they’re fully cooked. The only thing to bear in mind is that big, fat plump oysters take longer, so check if the biggest ones are done all the way through by cutting into them – the middle should be steaming hot.
Canned Oysters are usually smoked (covered later in this article) or fresh/boiled. These are safe to eat when you’re pregnant because the oysters are cooked as part of the canning and sterilization process.
Chargrilled oysters get queried a lot as people wonder: are chargrilled oysters fully cooked? Most chargrilled oyster preparations, and those found in restaurants, ARE fully cooked and are therefore safe. If you’re not doing the cooking, check if the oysters are fully cooked rather than simply charred or ‘seared’ on the outside.
Oysters Rockefeller – usually safe for pregnant women and those wishing to eat cooked oysters, as the oysters are topped and baked until cooked . I’ve eaten the original recipe at Antoine’s in New Orleans and it was fully cooked – and delicious.
Oysters Kilpatrick – This involves broiling or grilling the oysters, usually to crisp up a bacon topping, so they can sometimes still be undercooked underneath. If you’re making oysters kilpatrick, follow the cooking guidelines for broiling below, and if not, just check they’re done under the topping.
Cooking Oysters at Home: How to Make Them Safe
Below are the different cooking methods for oysters, and the times/temperatures required to kill bacteria like Vibrio vulnificus.
Cooking oysters according to these instructions should make them safe to eat if you’re pregnant. Overcooking oysters can make them rubbery and unpleasant, so precision is a good idea.
If you haven’t got one already, I recommend using a food thermometer (my recommended ones are here).
|Cooking Method||Time / Temperature|
|Frying||In oil, 3 minutes at 375F / 191C|
|Boiled / in soup or chowder||3-5 minutes, until edges curl|
|Chargrilled (Broiled / Grilled / BBQ)||3 inches (7.62cm) from the heat source for at least 3 minutes|
|Steamed||4-9 mins (longer for bigger oysters) after the water reaches a steaming point|
|Baked / Roasted||At least 10 minutes at 450F / 232C|
I ought to mention here that live oysters always close their shells when tapped – check them first, and discard any dead (non closing) oysters.
Can I Eat Smoked Oysters When Pregnant?
Smoked oysters often come in jars, tins or cans and are safe in pregnancy as they’re cooked as part of the canning process.
Oysters found at ambient (room) temperature, such as on supermarket shelves instead of in a fridge, are also likely to be sterilized and/or pasteurized and are safe to eat.
Avoid cold-smoked oysters during pregnancy. These are deliberately kept cool during the smoking process, so the smoke flavor is imparted, but they’re not actually cooked. They’re pretty hard to find and you only really come across homemade ones.
Hot smoked oysters are safe to eat, as they’re cooked during the smoking process. They’re typically smaller, as they shrink during cooking. These are the ones usually found in cans or jars.
Are Oysters High in Mercury?
Oysters are typically very low in mercury. The FDA’s mercury measurements from 1991 – 2009 state that oysters had, on average, 0.012 PPM (parts per million) of mercury (source: FDA).
The measurements don’t say whether the oysters were wild or farmed, however, the Environmental Defense Fund does make this distinction and have given a “low” mercury rating to a wide variety of oysters (source: EDF) including:
- Farmed Oysters
- Wild Oysters
- Pacific Oysters
- Eastern / American Oysters
- “Edible” Oysters
Unless there’s been a waterways advisory in your area, you can presume that these oysters are, on the whole, very low in mercury.
Are Oysters Good for Pregnant Women? What Are The Benefits?
Since cooking oysters make them OK to eat if you’re pregnant, you may also have wondered if there are any particular nutritional benefits from eating oysters.
Oysters are packed with vitamins and minerals, many of which are beneficial during pregnancy. They are a great source of omega 3 fatty acids, zinc, copper, selenium, manganese, iron and vitamins B12 and vitamin D (source: USDA).
Oysters are typically low in fat (around 3 grams per oyster) and have around 7 grams of protein as a complete protein, meaning they contain all amino acids essential to humans (source: WebMD).
The bottom line is – if they’re cooked in a healthy way (steamed, for example), they can be an extremely nutritious option as part of a pregnancy diet.
Can I Eat Oyster Sauce When I’m Pregnant?
Finally, I’ll address a popular Chinese condiment used in Asian recipes, and that’s oyster sauce.
Depending on the manufacturer, sometimes oyster sauce doesn’t contain oysters at all – sometimes it’s merely a flavoring, so check the ingredients.
Most quality oyster sauces will list “oyster extract” as an ingredient, in varying amounts depending on the brand.
Either way, oyster sauce is safe during pregnancy (whether it contains real oyster extract or not), as the oyster extract is from cooked or otherwise processed oysters – and the sauce itself is safe.
If you love Chinese food, you might also be interested in this article I wrote about eating out when pregnant, including Chinese takeout.
If you’re looking for more nutritious seafood options during pregnancy, you may also like:
- A pregnancy guide to eating shrimp and prawns
- Whether or not crab (and imitation crab) is safe for pregnant women
- A guide to eating scallops during pregnancy
- Everything you need to know about mussels and clams
- A guide to eating lobster when pregnant
This article has been reviewed and approved for publication in line with our editorial policy.