Baby under 10th centile 20 week scan

[Fipfop]

Hi, wondering if anyone has any experience of this. Had my 20 week scan a few weeks ago. We had a scan done privately at 16 weeks and baby was around 33rd centile. By the 20 week scan baby was measuring between the 7th and 10th centile.

I have low Papp a so already knew that we were at risk for low birth weight however I wasn't really expecting any issues until the third trimester.

The ultrasound tech wasn't concerned. Growth scans will start from 28 weeks but only because of the low papp a. Just concerned as this doesn't give the baby much wiggle room for loosing weight if placenta starts to be an issue in the third trimester. Also my first baby was 75th centile so this was a shock.

Any experiences of what birth weight to expect at this centile? Did people make it past due date or were you induced? If there's anyone who also had low Papp a would mind sharing how their baby progressed as the pregnancy went on when already starting so low that would be really appreciated. Thanks 🙂

Hi I had low Papp a. My baby was on the 10th centile the majority of my pregnancy. At my last growth scan it had dropped so I was induced at 38 weeks. He was 6lb 8oz and we went home the same day x

Hi,

I had low Papp A during my first pregnancy (think around 0.2) and my son was consistently below the 10th percentile when we had the additional growth scans. I think he may have been around 5th percentile but I would have to go back and find my notes. The consultant at the time didn't seem overly concerned as he was consistently small and stayed on the same trajectory. I must add that I'm 5ft2 and my husband is 5ft8 so I wasn't expecting a big baby! He's nearly two now and is still small but consistently tracks along the same percentile.

My son was born prematurely at just over 35 weeks and was under 5lbs but he's perfectly healthy and we only had a short stay in hospital for jaundice. No cause has been identified for the early birth and I'm currently pregnant again and under a preterm birth clinic. I'm honestly not sure what part the low Papp A played in all of this and anyone I spoke to who had low Papp A seemed to have a very normal pregnancy with no issues. That is certainly what my consultant, Papp A is such a new measure and the majority of women who had low Papp A will have perfectly normal healthy pregnancies. I think there's also so much room for error in the growth scans! Particularly when they are done so early on as yours at 16 weeks. I suspect they will count you 20 week scan only and as long as further growth scans show no decline in percentile then they won't be concerned. You should be seeing a consultant for these and I found mine very helpful.

I haven't found out if I have low Papp A yet in this pregnancy but honestly if I did it wouldn't be something that worried me.

Hopefully someone will be along soon who had low Papp A with no issues, I honestly seemed to be one of the only people I could find who had an early labour and small baby so not sure how representative I am! X

My daughter was 19 percentile at the 2p weeks scan and was born almost 9 pounds

Hi OP. No issues with Papp A but both my babies were SGA.

One born on the 4th percentile and one born on the 9th.

Both happy and healthy thriving pre-schoolers although DC2 is still rather petite sitting around 10th percentile for height and weight.

Thanks for all your replies! Looks like maybe looking at baby arriving a little early then! Really reassuring that even though babies were small they were healthy!