Yes, it happened to me with my third child. I was eating, maybe a little less, but more than most people, I felt that the baby was against my stomach giving me my own version of the lap band. The doctor said as long as I was eating she wasn't concerned that I lost weight during the entire pregnancy, the baby takes what he needs first, in this case mom comes last, if you aren't feeling the affects of not having enough to eat you can be doubly sure that the baby is fine. I probably lost 40lbs when I was pregnant with my 3rd child and only son, who is now a very healthy, good looking, smart, muscular 18 year old who is also mature for his age and has given us very little trouble. Relax, the baby is taking some of your nutrition, so you are not gaining, most moms start craving and eating everything, your diet hasn't changed, so think about it, you stay the same weight with baby gaining, you'll probably look like you lost weight when it's born, CONGRATULATIONS, WHOOOO HOOOO! You won!