Pregnant women can enjoy cooked oysters as part of the two six-ounce servings of low mercury cooked seafood they eat per week. Due to high levels of mercury, the FDA recommends a limit on the amount and kind of seafood pregnant women ingest to prevent harm to themselves and their baby. According to the American Pregnancy Association, oysters are in the class of seafood considered to have the lowest amount of mercury. Additionally, pregnant women should only eat oysters if they are fully cooked. According to the FDA, pregnant women should not eat any raw or undercooked seafood and should cook oysters until the shells open. If the shells do not open, those oysters should be discarded.