Because pregnancy affects your immune system, you and your unborn baby are more susceptible to the bacteria, viruses, and parasites that cause foodborne illness. Even if you don’t feel sick, some “bugs” like Listeria and Toxoplasma can infect your baby and cause serious health problems. Your baby is also sensitive to toxins from the food that you eat, such as mercury in certain kinds of fish.
Keep this checklist handy to help ensure that you and your unborn baby stay healthy and safe. And invest in a food thermometer to check the temperatures of cooked food. source
Foods and Beverages to Avoid During Pregnancy