Big weight drop between growth scans, but nobody seems concerned.

[BedHog]

I had a growth scan at 32 weeks, which showed the estimated fetal weight at 4lb 6oz, bang on 50th centile. All other measurements were average/large.

However, at my follow up growth scan at 36 weeks, the estimated weight had only increased to 5lb 3oz, roughly 2nd centile, and all the other measurements except the femur length were tiny too. The notes say 'normal growth since previous scan', but how can that be right if the estimated weight has increased by so little?

Shortly before the second scan, I had a midwife appointment where my fundal height was measured at 99th centile .

I know none of the measurements are particularly accurate, but if a newborn dropped from 50th to 2nd centile in 4 weeks, HVs would be really concerned. Why did both the sonographer and my midwife say there was nothing to be concerned about with these measurements? And if growth scans are so inaccurate that a 50th to 2nd centile drop is of no concern, then why do they bother doing the scans at all?

I havent had multiple growth scans so not quite the same situation as you, but did have one at 34wks as I was measuring 3cm large for dates at 28 & 31wks.

The scan showed head on 50th, tummy on 97th, couldnt find femur as baby lying in funny position. They said all fine & left it at that.

Since then, I have measured:

36cm at 34wks
36cm at 36wks
37cm at 38wks

So static / not much growth at all in last few wks AND was measuring big & now apparently measuring slightly small!

Baby still lying in funny position & hasnt moved into pelvis, so fundal height changes aren't due to that (I know sometimes fundal height increases can slow nearer term because baby moves down into pelvis, but this isnt the case for me).

I spent sunday night in hospital for monitoring due to baby's position & some uterine tightenings... had a quick scan by registrar plus numerous CTG's - baby seems totally fine. Nobody was worried / bothered about fundal height or growth of baby.

I think they look at everything as a wider picture. FWIW my daughter was born way over 50th percentile, and then settled onto the 2nd percentile after 4-6wks....she was just meant to be small, but presumably I ate masses of cake during preg & fattened her up pre-delivery!!

You could raise it with your midwife / consultant, but I would say if they aren't worried, then you shouldn't be either (I know easier said than done!)

Thanks Cheese - I've just spoken to one of the community midwives and she said that the 'normal growth since previous scan' comment suggests that there is nothing to worry about. I got the impression that they would be more concerned if just one of the measurements had significantly changed, for example if the overall baby remained the same size but the head circumference had grown off the scale. As all my measurements are still proportional, it could just be a slow couple of weeks growth, or variations in the scan (different sonographer, possibly different machine).

She did say to mention it again to my midwife next week, and she would refer me to a consultant if there was any concern.

I hope the rest of your pregnancy goes well - sounds like you're due any day!!