Since it is made from unpasteurized cow milk, Brie can be a host to the listeria bacteria. Listeria causes an infection known as listeriosis that can lead to serious complications like miscarriage, premature birth and even stillbirth during pregnancy. It can also lead to the development of birth defects in the baby. Pregnant women must consciously avoid eating brie during their pregnancy. However, if given the go-ahead by your doctor, it is considered to be safe for eating post pregnancy as it is a good source of certain nutrients.