My OB/GYN does not have an ultrasound machine in her office. She relies on the fundal measurement for measuring the growth of my baby. Yesterday I want for my check up. I measured at 25 cm and I am currently 30 weeks. She said that anything less than 3 cm is considered too small. She wants me to go see a Specialist to have an ultrasound to accurately measure her and to make sure everything is ok. She measured on target at my 20 weeks ultrasound.  With my first child I had to do this as well but I was 17 not gaining weight like I should and he was not measuring like he should have very early on. I was induced with him at 38 weeks and he was born 6lbs 1 oz. to this day he is on the smaller side of the growth curve. I have done everything right with this pregnancy. Have gained the adequate amount of weight.