Femur length declining, now 3rd percentile at 32 weeks

[fooolofbeans]

I have my scan measurements from 19weeks, 28 and 32 and baby's femur has not progressed like the rest of her body.

Crown to rump length at 13 weeks 53rd centile.

No concerns at anomaly scan, but femur 17th percentile and everything else around 50.

28+2 = femur 12th percentile and everything else around 45%

32+2 (today) = femur now 3rd percentile. Other measurements around 40%
Femur length has now dropped estimated weight to 6%.

No concerns with head, abdomen, amniotic fluid or umbilical artery.
I've been scanned by midwives then results reviewed by obstetrician.
Today's midwife was the pregnancy assessment unit manager, she took repeated femur length measurements but it was consistently the same.
The obstetrician isn't happy and wants to scan me herself but wants to wait two weeks to see if there is any change.
She wants to review as there is potential musculoskeletal concerns.
She did say it's probably inter scanner variability, but if this is the case why can't she scan me sooner?

I'm flipping between worry that's something wrong and calmness that scans are inaccurate all the time. I think it's the trend that's worrying me the most.

Does anybody have any experience or advice please? I don't think I can wait two weeks. Huge thanks I'm advance!

[fooolofbeans]

Bump before bed

[Sukitakeitoff]

I hope someone comes along who knows specifically about the femur measurement, but I didn't want this to go unanswered...

DD2 measured small for dates so I was scanned regularly. Eventually they thought growth might have slowed and that the head seemed disproportionately small. I googled (not always a good idea!) and worried about all the worst possible genetic causes.

I was induced just before my due date and other than being small she was perfect.

I hope things turn out the same way for you. You're right the scan measurements can be pretty inaccurate. Have they given you any indication what the reasons could be if the scan's accurate?

[fooolofbeans]

Thanks for the reassurance sukitakeitalloff I'm glad your DD2 was perfect ☺ its such a worry isn't it?
I've just rang the hospital and the obstetrician's secretary is on leave but I had a really good chat with the midwife who scanned me yesterday. She's going to speak with the consultant, and see if there's anything that can reassure me. The obsterician only has one antenatal clinic a week and it's on a Monday and next week is a bank holiday so the consultant couldnt see me sooner unless it was an emergency. The midwife said the potential risks are for achondroplasia or other limb dysplasia. She said that the bones looked well mineralised which was good as I was concerned that she could get an in utero fracture and be in pain but she said that absolutely isn't a possibility based on what she saw on the scans. She doesn't know of any private obstetrician's locally who could scan but said I could pop in to speak to her for reassurance if I'm getting anxious. She's going to ring me if she manages to speak to the consultant. Phew deep breaths!! Can someone teleport me to a Caribbean beach and put a (virgin) mojito in my hand please?!

[RNBrie]

Well done for calling and talking in through with the midwife. I think you should be reassured that you're not being seen as an emergency and that the consultants are happy to wait.

A close friend of mine recently had a baby who had multiple red flags during her pregnancy. They had a whole team of consultants seeing them regularly throughout the pregnancy. I know it was very hard on both her and her husband and she really struggled to enjoy being pregnant. When her dc was born it transpired that only one of the red flags was anything to worry about and her dc has the mildest form possible of the problem. She might never experience any issue because of it.

I know it's impossible to relax when these things are happening, I guess all you can try and do is distract yourself and the time will pass until your appointment.

[Sukitakeitoff]

I guess it's just a case of waiting now then - to speak to the consultant and for the next scan. Think positive!

[imjessie]

Would you terminate if there was a problem with your baby ? If so have a amnio Ans request they do a micro array on the babies genetics . My son had a short femer and it was dismissed . He has some issues , a short femer isn't always a sign of a genetic problem but can be .

[PretendingToBeAMuggle]

Foool here, I've name changed. I wouldn't terminate unless it was something that would severely impact on her quality of life and /or cause a lot of pain, so have pretty much ruled out an amnio unless they strongly suspect an abnormality. I've had the obs scan and she seemed quite happy that there were no abnormalities present and femur was measured at 12th centile this week. She's not growing great overall so another growth scan booked to see how things are going in a fortnight.
Is there a genetic cause of your sons short femur jessie ? It's great that they can potentially pick things up on the scans but I think we've just reached a stage where theyre just being stressful rather than informative. The scans seem to be taken with a pinch of salt due to their potential inaccuracy and doubt there will be anything definite before she's born unless her growth appears to tail off further

[imjessie]

Yes there is , he has a genetic ( unseen before ) . We had a rocky pregnancy and had a cvs which showed he was fine . He isn't fine but he is healthy and that's ok but he will be an adult with fairly severe learning difficulties. I don't want to scare you but just take their advice and look into it ..

[PretendingToBeAMuggle]

Thanks it's so difficult knowing what to do for the best when everything is so uncertain. Can I ask did you have the CVS solely due to the short femur or did they identify other potential risk factors?

[imjessie]

We had high odds based on my bloods for Edwards syndrome . His scan and Nuchal was fine . I would have terminated if he had Edwards so we had the cvs based on that info . His short femer was the only thing that was questioned because a lot of children with genetic issues have are of short stature . I'm only 5 ft so they just said is because I'm short but my husband is tall and so it out daughter . And it was something ridiculous like in the first 3 % so very short . He still has short legs and is little overall .

[Babydreaming]

I had a very similar experience! Femur length was on 40th centile at 20 weeks. Had an extra scan for other reasons at 30 weeks and it dropped to 10th and then by 36 weeks it was on 2nd centile!! My baby also had a kidney problem so they were highly suspicious of a genetic abnormality! I had an ambio which came back normal.

I now have a 5 month old baby. He's had a few issues (related to the kidney problem and also a cows milk allergy) but seems otherwise healthy! He was born at term and was 6lb15oz and length on the 20th centile! He looked no different from any other newborn!

I spent my whole pregnancy stressing about the femur length and that my baby would have a skeletal problem...all that stress for nothing!

He's still really little compared to his peers but I think that's more been due to poor feeding due to cows milk protein allergy

[Shayer]

Hey i been told my baby had short femur under 5th percentile all during my mrs pregnancy, and efw under 5th percentile as well, my baby boy just got out tonight healthy n fine, ive been reading all these posts here and beeen worried all throught till he came out, dont worry about nothing, ur baby is gona absolutely fine, gud luck

[GirlcalledJames]

For other reasons had a two scans at different places in four days at 35w, one put her on the 84th centile and the other on the 24th centile. There seems to be a lot of operator variability. Between 20 weeks and 35 there was a difference of 70 centiles in the femur length. I would guess there's a chance that nothing is wrong.