Advice on femur length please

[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!

I know this is such a stressful time. Try to remember that growth scans are fairly common in pregnancy - I had several in my first pregnancy and DS was just fine. He wasn’t the biggest baby, I think he was on the 25th centile overall but totally fine.

Any measurement that is inside the centile lines is normal. If you got 100 babies of the same gestation yours would be the second or third baby in the ‘line up’ for femur length but that could well change in the next few weeks and, as I say, anything within the centiles is fine. Most babies will measure around the average in the middle, some smaller some larger. Every child will grow and I don’t think height becomes properly predictive (I.e. possible to use to estimate how tall a child will be in the future) until at least 2 years.

I’m sorry that they didn’t make clear to you that you need to come back in 2 weeks but that in itself is nothing to worry about. On the contrary, it’s really good that they’re doing two scans because then they can look at growth over time.

Even if baby isn’t growing as fast as they should be there are lots of options for managing this. They can monitor you more closely, offer more scans, have a look at your placenta and, if absolutely necessary, plan to deliver baby early. That won’t happen unless they are clear something isn’t quite right and you are at a really good gestation already, where babies have good outcomes.

I know it doesn’t help to say this but try not to worry. Chat this over with your midwife if you can - they may be able to reassure you.

I was having growth scans and used to worry about my babies measurements - his head was on the 100 percentile and legs down on the 2nd percentile. Each scan she would ask if my partner was tall - we are both nearly 6ft.

The key stat was the baby was growing between each growth scan.

I gave birth to a baby with an average head size and long body and legs!

Thanks both for replying! It’s so worrying isn’t it but I know I need to try not to. It’s reassuring hearing about your experiences

I'm 33 weeks pregnant and having scans every 2 weeks due to short femur length, babies legs are measuring below the 3rd centile, his head and abdomen are measuring fine and his growth generally every 2 weeks is consistent.
I have seen fetal medicine and they have put it down to small genetics on my side, we are a small family lol and my son who's now 15 is still small,
Assuming this baby will just be the same xx

Thank you for replying! I’m really hoping we are the same. As you said, we are a small family too so I was never expecting her to be tall lol but your worries get the better of you!

Currently on the same situation- how was your journey eventually? Hope all is well
For You and your LO 💙🙏🏻

He was born at 36+ 6 weighing 4lb 1, so small even for the gestation, he spent 48hrs in NICU and then discharged. He is now nearly 2, still short in height (as am I) but on 50th centile for his weight. Otherwise all is great :-)

@crobo87 hey thank you for reverting - congratulations this is such good news🌼 wishing u all the best and reading such positive news really helps. May u always be well 🙏🏻

Hi all,

hope it’s okay to ask a further question on this thread…I’m new here!

I had a scan yesterday and the femur length was in the 7th percentile. Everything else what between 40-50. I haven’t been asked to come back for growth scan because it is literally just on the line, like the diamond shape isn’t even fully on the line half is off..if that makes sense. I’m worried because if it was even slightly less I would have been called back.

will the holiday rescan me if I request it? I feel like they don’t really like to do so

thank you!

Hello - promised i will respond to most threads after labour. I had similar issues with short femurs (even below 3%) during last weeks of my pregnancy, even the day before i was induced. I also did amnio to exclude skeletal dysplasias. Thankfully all was well, baby is thriving🙏🏻 was born above average kg and height. But, No doc could 100% tell me all is fine, but were telling me not to worry. I know its easier to say than actually stop stressing over this, but pls dont worry and do whatever will make you feel better. (Ask questions, additional ultrasounds etc)

Hi
thank you so much for your reply! I’m so glad everything worked out for you and your little one. I actually called the hospital back and asked to speak to a sonographer other than the one who scanned me. The one I spoke to was really lovely and she said that they had already booked me in for a 28 week growth scan..I wasn’t told this at the time so I feel better now I know they will check again. :)