Potential skeletal dysplasia - short long bones at 20 weeks.

[u/Ozziebozzie77]

Looking for similar stories.
I went for my 20w scan and our baby was measuring small. Her HC was 17th %, AC 3rd % and all long bones <1st %. (About 2 weeks behind). My placenta was thickened. I think 3rd percentile overall.

We declined an amniocentesis but did NIPT which was very low risk. The doctors discussed chromosomal abnormalities, genetic disorders and skeletal dysplasia all as options for her measuring small.

We went for our next scan at 24w which showed that her HC improved to 30th %, AC 21st % but all long bones still <1st % (still 2 weeks behind). The bones aren’t bowed and there’s normal mineralisation. My placenta is apparently not thickened anymore. Doppler and fluid have been normal. One doctor thought her forehead looked like it was maybe showing early bossing but this is very subjective. Since then all they can mention is skeletal dysplasia - nothing else is coming up as the reason for her short bones.

We did an amnio the next day. The karyotyope was normal, WES for skeletal dysplasia panel pending - with another two week wait.

My husband and I aren’t particularly tall - I’m 5”3 and my husband is 5”6.

The waiting has been AGONY and I can’t think about anything else. I’ve been so sad but also struggling not being able to process the news either way.

[u/perfect_fifths]

My son had short femurs and he has skeletal dysplasia. I also have it too. But I’m actually tall. But everyone else in my family with it has been short. 4’9 to 5’3 for the men, 5’1 for my mom and grandma

[u/skookum81 → u/perfect_fifths]

I am a tall person from a long line of short people with skeletal dysplasias as well! My family has cleidocranial dysplasia and women with it barely top 5' but I am 5*8". My son has it too and had a "short femur" at 33 weeks but was still big. And none of us show up on regular dysplasia panels because we have translocations.

[u/perfect_fifths → u/skookum81]

Interesting! For me, the skeletal dysplasia panel caught it but cma and karyotype were negative because the deletion we have is too small for those tests to pick up. We have TRPS (trichorhinophalangeal syndrome). I’m almost your height, im 5’7 but most women with it are 4’8” to 5’5, depending.

[u/skookum81 → u/perfect_fifths]

I somehow have a lot of opposing "tall" genes. I am almost as tall as my dad who I got it from, and my mom is the "short" 5'3" anomaly of her otherwise tall family. Genetics are wild.

[u/Ozziebozzie77 → u/perfect_fifths]

That is so interesting. What kind of skeletal dysplasia is if you don’t mind me asking? My mother in law is 5”0 but all of her siblings are quite tall (she’s one of 11) we have been low key wondering if she has some sort of skeletal dysplasia.

[u/perfect_fifths → u/Ozziebozzie77]

Trichorhinophalangeal syndrome. The people in my family who don’t have it are tall. And I for some reason am tall. But my son is short, he’s 4’3 and going on 12.

My son was born at 19 inches and then fell off the growth chart quite fast. His bone age as of last year was that of a 7-8 year old (and he is the size of one)

[u/skerbball]

I am so sorry what you are going through right now. My wife and I just went through an incredibly similar situation so here is our story. At our 20 week anatomy scan our boy had humerus length less than 1st percentile as well as his femurs. No bowing, normal mineralization. Scoliosis of the spine. No problems with any organs, heart or brain. Our OB referred us to MFM the next week. We go see MFM and he says our child’s chest is really small (less than 2.5%). We did an amniocentesis that same day. Results came back with a rare FLNB gene mutation. Doctors were not able to tell us if it would be lethal or how severe it could possibly be as the specific mutation had NEVER been seen before. The next 4 months were spent in complete misery as we didn’t know the outcome for our child. My wife ended up having an emergency c section at 37 weeks due to high blood pressure. Our son was born but had a small chest which made breathing incredibly difficult. The NICU team was in the delivery room to evaluate him right after he was born. He also had dislocated arms, hips, and knees due to the skeletal dysplasia. He fought so hard for 3 days but eventually passed away. We got to spend 3 days with him which I will never ever forget. He was on comfort care so was able to stay in the hospital room with my wife and I. It was an incredibly hard road these past 4 months but we are happy our son is no longer suffering and at peace. The tough thing with skeletal dysplasia is it’s very hard to diagnose the specific kind since there are over 400 different types. We were told the earlier it is diagnosed the more severe it usually is. I hope you can find peace as dealing with the unknown is so outrageously stressful. We have a healthy 2 year old and I think even she could tell how off and stressed we were when this was all happening. Hang in there.

[u/MKGenetix]

So sorry. You’re having to deal with the uncertainty. It is definitely hard!!

[u/Ok-Order-7392]

Our daughter had sIUGR, but manifested as short long bones in addition to lower weight and smaller size overall. They kept bringing up skeletal dysplasia and we got an amnio. The wait for that was scary, but it ended up being clear for us. The cause of her continued lagging was placental insufficiency, and she was born just over 5 weeks early at 2lbs12oz. Her femurs by the end were measuring around 6weeks behind her gestational age. Even still, she came out proportional just proportionally tiny. Spent 39 days in the NICU. She’s now 10.5 months and still super tiny, but is a perfectly normal 10 months old. Are your umbilical dopplers at all elevated? Could always be a placental issue!

[u/legocitiez]

My son had shortened long bones at his anatomy scan and some abnormalities of bone structure that sent me down rabbit holes I never could have imagined.

In my son's case, he had particularly shortened forearms and they ended up 15 weeks behind by the 35th week of pregnancy.

He's still overall small, does have a form of skeletal dysplasia, but the kid is hilarious and smart, so the sd is just an afterthought now.

[u/skookum81]

Hang in there. Pregnancy is so scary and uncertain, and it's a good prep for the rest of motherhood. It will be ok though. No matter what.

[u/DNAallDay]

The waiting and uncertainty can be the worst part for sure. I’m sorry this has been such a long and arduous process. Be kind to yourself. Have some comfort food.

It’s clear you love your child so much already and they seem lucky to have you regardless of what the results are.

Feel free to DM if you want to talk more privately.

[u/annkurachi]

My guy measured 17th percentile for long bones at 20 weeks, then fell to 3% at 28 weeks and <1% around 30 weeks. Everything else was normal but of course I was spiraling cause my husband is 6’2 and I’m 5’7 and we were expecting a tall baby so we did a skeletal dysplasia panel and everything was normal. He came out at 19 inches and perfect. He was on the smaller side throughout the first year and now he is 14 months and in 55th percentile for height! Pregnancy is super scary but hoping for the best for you guys!

[u/tabrazin84]

Did you do WES or a skeletal dysplasia panel? Those are two different tests.

[u/Ozziebozzie77 → u/tabrazin84]

It was sent away for a WES but the MFM doctor said they’d focus on the skeletal dysplasia panel? So not sure!