Scans with Miss I the whole way through put her as way ahead of dates. The scan I had at 32 or 33 weeks indicated from hc and limb length that she was going to be a very large baby. She was born at 40+5 weighing 3.5kgs and 50cm long - smack on average. Scans with Miss A put her as being a little on the small side. She was born at 41+1 at a smidge under 4kgs.
SIL was induced at 38 weeks because scans indicated her baby was small and the OB was concerned about the placenta's effectiveness. He was born at 4.2kgs
I wouldn't put too much faith in them TBH, certainly not from my experience.
My scans were all pretty much perfect for size. My ob has an ultrasound machine in his room and measures bub's head, tummy and thigh and the ultrasound machine estimates gestation and weight. With each bub my last scan before birth was no more than a week before, and the estimated weight was always pretty close to birth weight.
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