I started measuring smaller (according to the doctor) at around the 27wk mark too, and didn't really catch up with what measurements "should" be (I am nearly 6ft tall, have a long waist and baby engaged early). I was two extra ultrasounds - one at 28wks and another at 34wks to check growth. Bubs is still on the smaller side, just measuring on his own growth curve. We've think he'll be long and lean like his parents.