My 3 year old had some dental work done today (1 extraction and 2 fillings) and apparently the dental assistant didn't realize I was pregnant until it was all said and done. He has a bit more work to do in a couple of weeks, and she said I can't be in the room next time because of the nitrous oxide exposure. Should I be concerned that I was in there with it for about 35 minutes today? She didn't seem too concerned and said the dentists still work around it when they are pregnant and that it's just a liability issue for me to be present from now on.