Small bump and baby

The measurements aren't accurate as it's all dependant on baby's position that day

I was told at my 25 week appointment that +/- 2 cm for how many weeks pregnant you are is considered okay as the measurements aren't accurate. However at my 29 week appointment the measurement was -3 cm and has now crossed over the line on the chart so it has triggered a growth scan.

You can ask if you are concerned, but it might be that they are waiting for your next measurement to compare growth a bit more accurately on the chart to see if there is a concern.
They didn't seem concerned that I was meausring -3 more that the growth hadn't followed the expected rate on the chart if that makes sense

Yes I said if it was enough to warrant a scan but said she wasn't concerned for now

Mine went down a cm instead of up 3cm so now I am also waiting for a scan but the midwife wasn’t worried. I read it could be because of the baby’s position but also different people measured it each time

It wil have been plotted on a chart, it will depend how the chart looks not what the number of cm is. Do you have access to your notes online so you could have a look? When they measure they look for the growth to measure the trajectory x