I had my 30 week ultrasound this morning. Baby A and Baby B had been very similar in size up until this point. Now Baby A is a half a pound behind. The doctor thinks his/her placenta is not delivering enough nutrients. I have to go to the hospital twice a week for non stress tests now. I'm worried I won't make it far enough or that they may not catch a serious problem quick enough. The doctor told me to be diligent in making sure they both, but especially Baby A, move four times an hour. I have been okay up until now, but now I'm really scared.