Pregnancy week by week

You want what's best for your baby. That's why you might do things like add sliced fruit to your fortified breakfast cereal, top your salads with chickpeas or snack on almonds. But do you know what foods not to eat during pregnancy? Here's some basic information about eating during pregnancy.

Don't eat seafood high in mercury

Seafood can be a great source of protein. And the omega-3 fatty acids in many fish can help your baby's brain and eye development. But some fish and shellfish have levels of mercury that could be harmful. Too much mercury could damage your baby's growing nervous system.

The bigger and older the fish, the more mercury it's likely to contain. The U.S. Food and Drug Administration (FDA) says not to eat the following while pregnant:

• Bigeye tuna.
• King mackerel.
• Marlin.
• Orange roughy.
• Swordfish.
• Shark.
• Tilefish.

So what's safe? Some types of seafood have little mercury. The Dietary Guidelines for Americans advises pregnant people to eat 8 to 12 ounces (224 to 336 grams) of seafood a week. That's 2 to 3 servings. Here are some options:

• Anchovies.
• Black sea bass.
• Catfish.
• Cod.
• Freshwater trout.
• Herring.
• Light canned tuna.
• Oysters.
• Pollock.
• Salmon.
• Sardines.
• Shad.
• Shrimp.
• Sole.
• Tilapia.
• Whitefish.

Don't eat raw, undercooked or tainted seafood

To avoid harmful bacteria or viruses in seafood:

• Don't eat raw fish and shellfish. Examples of raw or undercooked foods to avoid include sushi, sashimi, ceviche and raw oysters, scallops or clams.
• Don't eat uncooked seafood that's refrigerated. Examples include seafood labeled nova style, lox, kippered, smoked or jerky. It's OK to eat smoked seafood if it's in a casserole or other cooked dish. Canned and shelf-stable versions also are safe.
• Watch for local fish advisories. If you eat fish from local waters, check for fish advisories to see how often you can safely eat those fish. Make sure to do this when water pollution is a concern. If you're not sure about the safety of fish you have already eaten, don't eat any more fish that week.
• Cook seafood well. Cook fish to an inside temperature of 145 F (63 C). Fish is done when it flakes with a fork and looks milky white throughout. Cook shrimp, lobster and scallops until they're milky white. Cook clams, mussels and oysters until their shells open. Throw away any that don't open.

Don't eat undercooked meat, poultry or eggs

During pregnancy, you're at a higher risk of food poisoning from bacteria. This is called foodborne illness. How your body reacts to food poisoning when you're pregnant might be worse than if you weren't pregnant. Although it's rare, food poisoning may affect the baby, too.

To prevent foodborne illness:

• Fully cook all meats and poultry before eating. Use a meat thermometer to make sure.
• Cook hot dogs and lunch meats until they're steaming hot. Or don't eat them at all. They can be sources of a rare but serious foodborne illness known as a listeria infection.
• Don't eat pates and meat spreads that are stored in a refrigerator. Canned and shelf-stable versions are OK.
• Cook eggs until the egg yolks and whites are firm. Raw eggs can have harmful bacteria. Don't eat foods that may be made with raw or partly cooked eggs. Examples include homemade eggnog, raw batter and dough, tiramisu, freshly made or homemade hollandaise sauce, homemade Caesar salad dressing and homemade ice cream.
• Don't eat ready-made meat salads or seafood salads. These include ham salad, tuna salad and chicken salad.

Don't eat unpasteurized foods

Many low-fat dairy products can be a healthy part of your diet. These include skim milk, mozzarella cheese and cottage cheese. But don't eat or drink anything that contains milk that hasn't gone through a process called pasteurization. Products that have unpasteurized milk could cause foodborne illness.

Avoid soft cheeses, such as brie, feta and blue cheese, unless the label says they're pasteurized or made with pasteurized milk. Don't drink juice or cider that isn't pasteurized.

Don't eat unwashed fruits and vegetables

To get rid of harmful bacteria, wash all raw fruits and vegetables well. Don't eat any raw sprouts, including alfalfa, clover, radish and mung bean. They might have harmful bacteria. Be sure to fully cook sprouts.

Don't have too much caffeine

Caffeine can cross to the baby, but the effects on the baby aren't clear. To be safe, your health care professional might tell you not to have caffeine while pregnant. Or you may be told to limit caffeine to less than 200 milligrams (mg) a day.

An 8-ounce (240-milliliters, or mL) cup of brewed coffee has about 95 mg of caffeine. An 8-ounce (240-mL) cup of brewed tea has about 47 mg. And a 12-ounce (360-mL) cola with caffeine has about 33 mg.

Don't drink herbal tea

Not much is known about the effects of certain herbs on fetuses. As a result, don't drink herbal tea unless your health care professional says it's OK. That includes the types of herbal tea made for pregnancy.

Don't drink alcohol

No amount of alcohol has been proved safe during pregnancy. To be safe, don't drink any alcohol.

Consider the risks. Drinking alcohol during pregnancy leads to a higher risk of miscarriage and stillbirth. Drinking alcohol also may result in fetal alcohol syndrome. The syndrome can cause the face to form oddly and cause lower intelligence.

If you're worried about alcohol you drank before you knew you were pregnant, or if you think you need help to stop drinking, talk to your health care professional.

Mayo Clinic's Ultimate Guide to Pregnancy

This guide offers research-backed advice to help you and your baby experience a healthy pregnancy, written by some of the world's leading medical experts.

Learn More