Dietary taboos The first three months of pregnancy are a critical period for the formation of the fetal organs and nervous system, so special attention is needed in diet. The following are dietary issues you need to pay attention to during early pregnancy. Foods that should not be eaten During early pregnancy, you should stay away from raw and cold foods, raw fish, raw meat and raw eggs, as these foods may be contaminated or contain parasite eggs. In addition, you should avoid eating seafood containing too much selenium, such as herring, crucian carp, etc., because excessive selenium intake may be harmful to the fetus.