# Large abdominal circumference at 20 weeks



## Cybele

Hi,
I had my 20 week scan (20+2) today, which all went well and  .  Her measurements are all within the normal ranges:
BPD 48mm
HC 178 mm
CM 5.1mm
FL 35mm (looks like she might be tall unlike mummy  )

but the abdominal circumference was 166mm which is the 97th percentile.  The sonographer said she was just likely to be a very big baby.  Is there much of a margin of error for the measurement?  And is it likely to change through the next 20 weeks, i.e. might she slow down?  
I've also read that large babies can be related to gestational diabetes, but no-one has mentioned that to me yet.  Should I ask my mw if I need to be tested?
Many thanks!
Cybele


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## emilycaitlin

Hi,

Don't worry, every person measures differently, and it's impossible to get a completely accurate measurement on a scan, your baby could be lying in a poor position for measuring also.

Gestational Diabetes isn't usually tested until 28 weeks, if it is thought necessary, and usually the whole of the baby grows large, and this would be apparent to your midwife during your routine checks.

Everything sounds fine, and if they had been concerned today, they would have booked you in for another scan,

emilycaitlin xx


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## Cybele

Thanks for putting my mind at rest emilycaitlin.  I'm really pleased that everything is measuring well, it's just the thought of a huge baby is scary!  
Cybele x


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