MSG can cause a number of problems in adults, and I can't imagine that it would be good for a developing fetus. When we order Chinese food, we always ask for NO MSG - pregnant or not. Some pre-made things (like egg rolls, or crab rangoon) may already have MSG. But if they are cooking you something like fried rice, meat, and vegetables, just tell them not to add any MSG. Most of the time my food tastes about the same, but sometimes I just have to add more salt than usual. (Mono-SODIUM-Glutamate)
I didn't really know about listeria in the lunchmeats and hot dogs. I have been avoiding them for some time now because of the nitrates and nitrites. These are hard on our bodies, and even harder on the bodies of children because their livers aren't as big as ours and therefore it takes them even longer to process. I buy Shelton's chicken and turkey dogs at the health food store, that have no added nitrates or nitrites. They are frozen and we boil them - so no need to worry about listeria with those I guess!