Monosodium Glutamate, or MSG, is used as a food additive for flavor enhancement. MSG is a sodium salt that works by intensifying and enhancing flavor, without contributing a flavor of its own.
The effect of MSG on unborn babies has been the subject of a large amount of studies. At this point, no studies have shown any damage or risk in human studies, although studies with mice have shown that high doses of MSG may cross the placental barrier and cause damage in brain development. In addition, research has shown that the placental barrier does not allow MSG to pass from a mother to her unborn child, so pregnant women need not be concerned about foods that contain MSG. Because of this lack of any toxic effects, MSG has been classified as being safe to eat during pregnancy.
The one concern about MSG during pregnancy is its sodium content. Although lower in sodium content than table salt, it still may contribute to water retention. If you are worried about how MSG might affect you or your developing baby, become aware of what foods contain it and limit your intake of them. Be a careful reader of ingredient labels and ask your server at a restaurant if MSG is used in preparing their recipes.