BPD and HC measurements

Hi all,

I know I'm being silly but any reassurance would help. Just had a scan at 28 weeks 5 days and BPD (head) was measuring big as usual (75th percentile) but the head circumference was measuring small (11th percentile, measuring 26 and a half weeks). BPD has been measuring big for a while but this was the first time I noticed the HC being small.

My OB/gyn who has a wealth of experience says there is absolutely nothing to worry about and I know that HC measurements are often very inaccurate but hormones are making me irrational!

Has anyone else got experience of this?