Femur length

[Chestermumtobe]

Good evening

I’m seeking advice as I’ve been crying for an hour and I need to try and stop for the sake of the baby.

At the 20 week scan nothing was highlighted to us and all seemed normal. Her femur length was 32mm. This week, the midwife sent me for a growth scan as bump was measuring slightly small at 31 weeks. She is now 54.1mm which is only on the 2.6 percentile. I have to go back in 2 weeks to ensure she is growing. She didn’t point this out to me, I’ve just read it in the report.

I know she’s growing as I also had a private scan at 28 weeks and she was 52mm but I’m just wondering if this is something I should be worried about or what it could indicate? Of note, I’m only 5ft 3 and husband is 5ft10. My mom is 4ft 11 and MIL is 5ft so we are hardly a tall family.

If anyone can shed some light or tell me about their experience I would be so grateful.

Thank you!

[Joxxjo]

I had 3 growth scans in total. They don't know anything based on 1 scan and need to see subsequent scans at a few weeks apart. Please don't worry a small baby isn't a sign on its own of an unhealthy baby. Plus growth scans aren't aren't an exact science. My baby measure 9th percentile and came out on the 25th percentile perfectly healthy where she's stayed ever since x

[Bigblueskies]

Hi

It’s worrying when these scans come up with odds measurements, I totally empathise. We had a few scares with our first baby and learnt the hard way to not take it all too seriously.

Scans are not very precise. Our daughter was measuring on the 6th percentile for head circumference which was terrifying to us. Her femur length was also on the small side, but both my husband and I are quite tall so completely at odds. We then had a scan with a consultant (much much more experienced at growth scans, they are a real art to get right) and all the measurements were normal but still on the lower half.

She was born completely fine! She was measured by ultrasound to be small but was actually born completely average, 50-70th percentile. She is now almost two and she is on the 95th percentile for height.

Unless you have an underlying condition, perhaps you need to take it all with a pinch of salt. It may be worth checking that the blood supply to the baby is ok (and are there the right number of blood vessels going through the cord), your haemoglobin levels to make sure you’re not anaemic, that the baby is generally in proportion (they are rarely in complete proportion but roughly) and that the amount of space the baby has is ok. My consultant prescribed baby aspirin (150mg per day) when we were worried about growth. She said it helps the blood supply to the baby, so if you’re not already taking it it’s worth asking about that.

Big hug and good luck! I hope they put your mind at ease soon.

[Jonesy84]

Hi lovely, at our scan babys tummy and head was measuring a couple of weeks ahead and his femur length was slightly behind. The scan lady said everything was normal and it was only because we stood talking for a bit and we asked about the sizing she mentioned it but said it's normal. We had another scan which was private and his head was on track instead of ahead tummy was still ahead but femur length had caught up. Baby sizes can change all the time. As for the bump size as you know after 20 week scan they just measure bump so anything even slightly under or over they would scan as there is only so much a tape measure can say.I hope the responses have made you feel more calm and all the best for the scan xxx

[Trying1234]

My baby measured the 10th percentile and she was actually pretty small when she came out but she was 3 weeks early too. She stayed on the 10th percent line so no one was concerned throughout my pregnancy. She’s caught up now she’s out, at 11 months she was in the 75th percentile.

I think try not think about having a scan as a bad thing because doing a scan in 2 weeks will hopefully show she is growing and if she is in the same percentile that is a good thing. I was told it didn’t matter that she was small as she was growing.

[Flora631]

Don’t worry about the femur length too much, they are most concerned with the estimated weight and which percentile that is onMy LG was under the 5th percentile for femur most of the way through so I ended up having scans every 2 weeks. When she came out she didn’t have little legs at all!

Hope you’re feeling a little less anxious about it, I know it’s hard not to worry.