Is it normal for Baby measurements to fluctuate?

[Vogue1992]

Hi,

I had a private scan at 18w 3d and the sonographer said I was measuring 18w 5d. Yesterday I had my 20w scan at 20w 3d but looking at my notes the Gestational Age based on HC and FL is is 20w and 20w 1d.

Is this normal? Has this happened to anybody else?

Sorry if this is a silly question, I'm a first time Mum so a bit clueless.

Babys have growth spurts rather than a steady growth so yes it is perfectly normal.

From now on i would focus on which centile your baby is and how it evolves.
But otherwise sounds perfectly normal...
Babies are not uniform. Like kids and adults, they each have their own characteristics so longer arms shorter legs, smaller heads... etc

They use 12 week scans to date babies because it’s much more accurate than doing it later on.

I had a 20 week scan where the sonographer took atleast 3 measurements for each part and took their time. I had to go back 2 weeks later because there was one measurement they couldn’t get due to baby position.

At the 22 week scan a different sonographer measured the parts they couldn’t get previously several times but he only measured everywhere else just once and still input that data to the system.

These second measurements weren’t anywhere near as accurate as the first! Showing quite different percentiles etc.

I’m fairly sure baby is growing just fine. It was just speedy measurement taking that meant they were less accurate. It could also have been baby growth spurts. I think it’s good that we don’t have growth scans every 2 weeks all the way through, I’d be a nervous wreck!

Thank you for taking time out to respond, 20 weeks actually matches with the date of my LMP but at my 12 week dating scan they put me slightly further ahead.

I have to go back in 2 weeks time due to the position of Baby, they were not able to check a few things so I’ll put off worrying until then :)

@PinkPlantCase totally agree with you RE a growth scans. Gosh pregnancy is such a worry!

It is completely normal and these scans aren't accurate.
Their measurements are based on the person doing the scan actually placing grids ect over the baby and the slightest movement in that grid changes it by days.

Perfectly normal, my baby went from the 48th percentile to 85th percentile in 6 weeks and was born perfectly healthy on the 25th percentile. These things are very much an art not a science.