Isolated short femur length

[passthemustard]

Hey, I've been reading lots of threads about small babies and low birth weight babies but I can't find any to directly address my concerns about my babies short femur length.

I'm 25 weeks and have regular growth scans booked until 36 weeks. He's measuring on the 50th centile for everything but femur length which is on the 9th centile.

I'm really worried about what this means. Doctors haven't really addressed outcomes but everything I've been told/read points towards a marker for trisomy/dwarfism. Although they say they are not testing further for dwarfism unless femur length is below 5th centile.

My 12 week screening came back low risk but it was less than 1/1000 for downs rather than 1/10000 and less than 1/500 for the other 2 tests. So low risk but not like 'really' low risk!

Isolated short femur length seems to indicate a 3 fold increase in restricted growth and pre term birth. As well as being markers for the above conditions.

I'm trying to be positive but I'd really like to hear from any other parents whose babies had isolated short femur length and what the outcome was.

Hi I had a similar thing with my little boy he was measuring normally for everything but femur length below 5th centile. They were concerned as possibly a marker for Down's syndrome but also said it could be small constitution or insufficient placenta, i was offered amniocentesis which I declined but paid privately for harmony test which showed low risk for ds and all of the other conditions. I was worried the whole pregnancy and had fortnightly growth scans, he was born completely normally and is now almost 1 and in 18-24 month clothes he's massive

@geordiegreek thank you! That's very reassuring. Hopefully it'll measure longer at the next scan. I was wondering if it was subjective to the sonographer. Like how accurate is it??

@passthemustard no problem at all I can imagine how u feel as I was beside myself with worry for the whole second half of the pregnancy (it was picked up at 20wks) thinking there might be something wrong, or that he'd look really odd with a normal size head/body etc and really short legs (know it's a silly thing to worry about but I still did), you couldn't even notice when he was born it's not like he looked out of proportion or anything.
I'm not sure how subjective it is, I had the Fetal medicine consultant scanning most weeks but then later on (after ds had been ruled out) she oversaw a normal sonographer doing the scans/taking the measurements and I had a few different ones of those and the femur always measured short, but they were looking at was it growing 'following the curve' of the growth more than anything and as it was growing steadily but smaller than the rest they weren't as worried as the pregnancy went on. I'd been warned about early delivery at 36 weeks etc if he stopped growing but he didn't, I ended up being induced at 39 wks for something totally separate (high bp)

I remember having scan with ds1 and they were concerned about femur length and even mentioned dwarfism. I had an amino but that was due to high risk of Down’s syndrome. DS ended up being 9lb 11oz and is now 20 and 6ft 2” so all turned out okay but I understand your worry. Hope everything turns out okay.