Had another doctor's appointment today and they measured the girls:
Baby A: 2 lbs, 11 oz
Baby B: 2 lbs, 14 oz
Baby C: 2 lbs, 9 oz

The average for a singleton at 29 weeks is 2 lbs, 6 oz so our girls are doing great! Everything looks good and the doctor thinks it is very possible that I will make it past 32 weeks. He said by 33 weeks the babies should be over 4 lbs and it would be really good for them to reach 4 lbs before they are born. At the rate they are growing I think they can reach 4 lbs even before then!