There are certain guidelines as to what to avoid eating during pregnancy:

•    Fish and shellfish: Certain fish may contain high levels of mercury, which can affect the baby’s developing nervous system. Avoid swordfish, marlin, and shark. Limit your intake tuna or salmon to two medium-sized cans of salmon or light tuna, one medium-size can of albacore tuna, or one fresh tuna steak per week. Avoid raw or undercooked shellfish such as oysters, mussels, prawns (shrimp), and crab.
•    Milk and milk products: Avoid unpasteurized milk and cheese. This includes cheeses such as feta, brie, Camembert, blue cheeses, and goat cheese. These foods may contain bacteria called listeria, which are harmful to unborn babies.
•    Raw sprouts and unpasteurized juices: Avoid raw vegetable sprouts (such as alfalfa, clover, and radish) and unpasteurized fruit and vegetable juices, as these may contain bacteria such as Salmonella and E. coli. These bacteria can cause serious illness in pregnant women and may also be passed on to the baby.
•    Raw or undercooked meats, poultry or eggs: Undercooked meat, poultry, and eggs can contain bacteria and parasites that can harm an unborn baby. Be sure to cook ground beef and pork to at least 160° F (71° C), roasts and steaks to 145° F (63° C), whole poultry to 180° F (82° C), and eggs until the yolk and white are firm, not runny.
•    Certain meats: Avoid meat patés, and all liver products because of the risk of listeria. Liver and liver products are rich in vitamin A, and high levels of vitamin A may also be harmful during pregnancy.
•    Prepared foods: Avoid ready-to-eat meats such as deli meats, patés, and hot dogs. Also avoid ready-to-eat dressed salads (e.g., potato salad or coleslaw) and packaged salads. These foods may contain listeria.
•    Caffeine: Caffeine crosses the placental barrier into the baby’s blood when you are pregnant or breast-feeding. Limit your caffeine intake to less than 300 mg in one day.
•    Avoid all alcoholic beverages if you are planning a pregnancy and while you are pregnant.
•    Nicotine: Smoking during pregnancy increases the risk of a baby being born prematurely and underweight. Stop smoking if you are considering getting pregnant; if you are pregnant, never smoke. Because of the health risks associated with second-hand smoke, avoid any smoky environments.
•    Some artificial sweeteners: Aspartame, sucralose, and acesulfame-potassium are used in many foods such as soft drinks, desserts, yogurt, fruit spreads, salad dressings, chewing gum, and candy. Although evidence shows that these artificial sweeteners are safe for pregnant women, use them moderately. Avoid using saccharin or cyclamates.