During the first trimester of pregnancy, it is important to be cautious about what you eat to ensure a healthy pregnancy. There are certain foods that should be avoided during this time due to potential risks they may pose to both the mother and the developing baby. These include raw or undercooked meats, fish high in mercury, unpasteurized dairy products, deli meats and hot dogs, raw eggs or foods containing raw eggs, and certain types of seafood. It is also recommended to limit caffeine intake and avoid alcohol completely. By avoiding these foods and making healthy choices, you can help promote a safe and successful pregnancy.