Pregnancy: How accurate are ultrasound measurements?

[aristocatz]

Had a 28 week ultrasound the other day & the tech took some measurements and said my baby is in the 84th percentile for her height!!! (weight was in the average range) This threw me for a loop a bit. My DH is tall & I am very short. Our current DD is totally average in height.

Just wondering if any of you received ultrasound measurements when you were pregnant and the measure ended up to be totally inaccurate?

I also wonder, will she remain in the 84th percentile through the rest of my pregnancy or can that still fluctuate and change?

 

[misse336]

I was never given height measurements or percentages. I did go to a neonatologist (specialist) at a maternal-fetal medicine practice with my second child. They had really advanced ultrasound machines (the ones where you could see hair/actual facial features/ect) and even with all of that technology the ultrasound weights were whatever weight they told you plus or minus a pound. A pound either way doesn't sound like much, but when they tell you your baby is 8.5 pounds and you realize that could translate to 9.5 pounds is sounds a whole lot worse.

No idea about how accurate the information is or if it will remain steady through the pregnancy, but know that the weight measurements they give you probably come with plus/minus a pound.

 

[Geoff_M]

The estimates are only "rough" ones and should not be taken as the final outcome. Right before he was born, they estimated #3 child at 8.5 lbs. He made his debut at an ounce over 10! My wife wasn't gestationaly diabetic with him either. Also what the baby might be now is no indication of future growth. Our #3 is 15 now and is short for his age and very slender. He's about a full head shorter than most of his peers.

 

[Happy Snowman]

Mine were very accurate for birth weight/height, but they did not translate into overall adult height/weight. Our oldest was in the 90th percentile for height and 80th for weight when he was born. As an adult he is 5' 8" and about 130 lbs.

 

[aprilgail2]

They didn't give me the height but they were not accurate AT ALL for weight. In my 34th week they told me my daughter was 6 1/2 pounds, when I gave birth she was barely 5 pounds! When they said at 34 weeks she was 6 1/2 pounds I did the math of her gaining 1/2 pound a week for the last 6 weeks I was so afraid I was going to end up with a 9 pound baby!

 

[Kimberle]

Not very. I had 2 done in the same day and they were very different.

 

[Lisa loves Pooh]

Had a 28 week ultrasound the other day & the tech took some measurements and said my baby is in the 84th percentile for her height!!! (weight was in the average range) This threw me for a loop a bit. My DH is tall & I am very short. Our current DD is totally average in height.

Just wondering if any of you received ultrasound measurements when you were pregnant and the measure ended up to be totally inaccurate?

I also wonder, will she remain in the 84th percentile through the rest of my pregnancy or can that still fluctuate and change?

My son was near 11 pounds. His ultrasound did not reflect that trajectory.
Nor does his current height and weight at 7 years old reflect where he was born.

My youngest was born in normal ranges, but her 1 year she was 0%. at her 4yo check up, she was finally up to 3%. For a couple of years, we were actually wondering if she might have dwarfism. But at this point, she is just small.

My doc also said sizing ultrasounds are not reliable.

 

[sam_gordon]

For the sake of argument, let's say the measurements are accurate, and there's no possibility of changes between now and the birth...

Why would an 84th percentile for height be scary? According to this chart, at birth, the 50th percentile is 19 3/4". The 75th percentile is 20 1/2", the 90th is 21". You're talking about a difference of just over an inch (compared to the 50th percentile).

 

[kmb584]

They didn't give me the height but they were not accurate AT ALL for weight. In my 34th week they told me my daughter was 6 1/2 pounds, when I gave birth she was barely 5 pounds! When they said at 34 weeks she was 6 1/2 pounds I did the math of her gaining 1/2 pound a week for the last 6 weeks I was so afraid I was going to end up with a 9 pound baby!

This. At 35 weeks I was told that my daughter was already 8.5 lbs. She was born at 39w5d and was 6.7 lbs.

 

[mom2rtk]

Had a 28 week ultrasound the other day & the tech took some measurements and said my baby is in the 84th percentile for her height!!! (weight was in the average range) This threw me for a loop a bit. My DH is tall & I am very short. Our current DD is totally average in height.

Just wondering if any of you received ultrasound measurements when you were pregnant and the measure ended up to be totally inaccurate?

I also wonder, will she remain in the 84th percentile through the rest of my pregnancy or can that still fluctuate and change?

Maybe he was slouching when they measured.

Seriously. There are things to worry about in pregnancy. This isn't one of them.

 

[alicat8]

i don't know about height, but I know the weight is way off. At my last ultrasound, they told me she was 7 pounds. When she actually came out (a few weeks later) she was 6 lbs 1 oz.

 

[Gracie09]

Mine was accurate within a couple oz. They never said anything about height. I did get leg bone measurements though.
They did use a fancy 3d ultrasound.

 

[Allison]

I would take anything like that with a grain of salt but I also don't see why 84% is anything that would throw anybody for a loop.

You've been through a pregnancy before, correct?

 

[Soldier's*Sweeties]

Mine were as accurate as they probably could be.

I was pregnant with twins and VERY small. When the babies were born they were 5lbs7oz and 6lbs2oz so pretty big for twins! They were really crammed in there.

I was getting one Level II Ultrasound a week for the last probably five or six weeks. They did the best they could, but they were off by about a half of a pound and an inch for each baby.

 

[Soldier's*Sweeties]

I would take anything like that with a grain of salt but I also don't see why 84% is anything that would throw anybody for a loop.

You've been through a pregnancy before, correct?

I would be way more concerned with a tubbier baby than a longer one!

 

[NewRVLady]

Take with a grain of salt-
In august when my grandson was measured AFTER BIRTH-they measured him wrong

For his one week checkup he 'grew' 1 1/2 INCHES!

Parents say he was VERY squirmy when being measured

 

[Colleen27]

Ultrasound measurements are rough estimates and vary a lot depending on the technician in my experience.

When I was pregnant with my youngest I had some minor blood sugar issues. Even though I fell a bit short of a formal diagnosis of gestational diabetes my doctor was very concerned about DD's size. So I had an u/s at 37 weeks. According to that scan, DD was already 8lbs. She was born at 39w and was the smallest of my 3 children at 6lbs 15oz birth weight. So much for that u/s estimate!

Also, long babies don't necessarily grow into tall kids. My longest baby was DD13 who is now a whopping 5'2" and not likely to put on more than another inch or two since she's already through puberty. Her 6" tall brother was shorter than her at birth but towers over her now.

 

[laughinplace199]

Maybe he was slouching when they measured.

Seriously. There are things to worry about in pregnancy. This isn't one of them.

 

[DaisyD]

I've never got a height percentage at ultrasounds. All 3 of my kids were almost 22 inches so they must have had a high percentage. Lol. Now only one is still tall. Other two are average to short. Not a big deal and don't know what is scary.

 

[mjkacmom]

Ultrasound measurements are rough estimates and vary a lot depending on the technician in my experience.

When I was pregnant with my youngest I had some minor blood sugar issues. Even though I fell a bit short of a formal diagnosis of gestational diabetes my doctor was very concerned about DD's size. So I had an u/s at 37 weeks. According to that scan, DD was already 8lbs. She was born at 39w and was the smallest of my 3 children at 6lbs 15oz birth weight. So much for that u/s estimate!

Also, long babies don't necessarily grow into tall kids. My longest baby was DD13 who is now a whopping 5'2" and not likely to put on more than another inch or two since she's already through puberty. Her 6" tall brother was shorter than her at birth but towers over her now.

I had an u/s with dd13 right before she was born, and they estimated her at about 7 pounds. She was 8.12, 21 1/2 inches. She is now in the 8th % for height, 3rd for weight. We are hoping for 5'1". Her older brother was smaller at birth, and is 6', 185, and still growing. He looks like a giant next to her.