All three of my boys were classed at IUGR. I am only 5'ft 3 or something like that and with my first was only very slim. I was approx at my biggest difference between weeks and fundal height I was 6cm below. ie at 35 weeks I was 29cm fundal height.

They induced me with both Kameron and Lachlan at approx 38wk. Kam was 6lb exactly, Lach was 6lb 7oz. Ashton came into this world of his own accord 4 weeks early. The scan 2 days prior told me he was 4lb 11oz. He was born at 5lb 13oz.

Please don't stress about it. If you baby is laying a different way from the previous week ie more forward, or more back whatever, this can put your fundal height out as well.