STMs: were the growth estimates correct?

[CaptainLeela]

I'm curious how accurate fetal weight measurements are. I've heard a LOT of stories about docs who estimate a baby's weight to be higher and then the baby comes out quite a bit smaller than what was estimated. This little lady has been measuring big the entire time and I'm a fairly small person (5'3") so I'm really hoping that chances are that they're over-estimating her growth. 
So, experienced mamas: how accurate was your doc's estimate about your previous babies weight? 

[willadiesel814]

Last ultra sound at I think 35 weeks had DS at 7+ lbs. He was born at 8lbs 4oz, but literally while I was on the surgery table they asked me to guess weight, and I said 8lbs 6oz, and everyone laughed at me and said he wasn't that big. Well uh.. yea he was.

[shmee]

I had an ultrasound as soon as I checked into triage when my water broke, I was 39w4d. They estimated that DD would be 9.5 lbs.

She was born 14 hours later, at 7 lbs 10 oz.

Don't put too much stock into it!

[la79al]

They had me get an u/s when I was about 37 weeks with DD2.  They estimated her around 8.5 lb.  She was born 39w5d at 7p14o.  

[emu0013]

I was having bio-physical profile US and then the next week a normal US with my OB with DD. The week before I had DD the OB was saying she was 4lb2oz; the day of my emergency c-section when I failed my Bio- Physical profile the specialist at the MFM office was saying DD was 3lb1oz. She was born at 35W and 4lb 8oz. I really think it has a lot to do with the tech and equipment.

[veenie]

I had a scan at 40 weeks wi th an estimate of 8.5lbs, DD was born at 41w6d weighing 7lbs9oz. They told me the scans could be off by 2lbs either direction the difference between 6.5 and 10.5 lbs is huge!

I think they estimate by certain bone lengths. DD was 21.5 in, so long, so that's why they estimated high, maybe?

[lexisophie55]

I had 20 ultrasounds. Most of the time they would gradually increase and seemed just fine. My doctor thought he seemed average the entire time.

He was born 10 days early weighing 7lbs 2oz. Right on track to be an average 7.5 lb baby.

[hotcoconuts82]

With my first, I had an ultrasound on my due date and dd was estimated at 6lbs. She was born 7 days later at 6lbs 15oz. So, I'd say that one was pretty accurate.

[mpiemont]

The weight estimates are always way off. Ok so maybe not *always* but I have never actually heard of 1 that wasn't overestimating things. My OB with DS1 was pretty close and said "He's about an 8lb baby" and when he was born he was 7lb 15oz. But don't put too much stock in it or go returning all your NB size clothes. And please don't let anyone "scare" you by saying the baby is huge. Those estimates can be way off...

[autumn907]

Meh, I take weight measurements with a grain of salt. Now, bone measurements I take to heart.

[purpleroses]

I kept hearing DS was going to be on the larger side, especially after I failed my one hour GTT (I passed the three hour) and because I gained a decent amount of weight during my pregnancy. I frankly don't remember the exact weight estimates, but remember thinking DS was going to be 9 lbs. or larger. He was exactly 7 lbs. at 38w6d (in other words, not considered premature). Having read a lot about C-sections and factors in ending up with one since I'm trying for a VBAC this time, it seems like there's a school of thought that OBs tend to overdiagnose "big babies" these days.

[lgsdesigner]

DS: Estimate was 8lb 4oz, he was 8lb 6oz.
DD: Estimate was 8lbs, she was only 7lb 8oz.

[flyinghorses6]

Usually we tell people the US can be off a pound in either direction. We do not use hem on labor and delivery as a very accurate tool. If someone is measuring big or small- serial Utrasounds tells us much more than just 1 random one.

[madams728]

DD's was not accurate. They told me 7 and a half, and she was 5.12 full term.

On the flip side, my cousin just had a baby and they were right on the money.

[jennadesigns]

I'd take it with a grain of salt. With my son, they were spot on - they said about 7 pounds 6 ounces and he was 7 lbs 3 oz when he was born.

With my daughter, my OB swore she was going to be bigger - he kept telling me he thought she'd be about 8.5 lbs. She was only 5 lbs 14 oz. when she was born.

[amelandre]

Not at all accurate for DS. Every ultrasound they're telling me he's measuring big. "Oh he's 95th percentile for weight, 98th for head size" and I was freaking out because DH and I were both 10+ lb babies.

DS was 7lbs 3oz and his head was only in the 65th percentile. Pretty darn average:

[jenari]

So, we only do the one ultrasound here at 20 weeks for the A/S and they don't usually even tell you anything about size at that point but I thought this was pretty cool - I had asked my OB if there was any way to tell if I was having a huge baby (since DH and his brothers were all 10+ pounds and I was terrified! Her answer was that based on my size and what she could feel of baby she would guestimate that if I went around my due date DD would be around 6 pounds and if I went over she'd be closer to 7. Well DD was born 41+1 and was 6 pounds 15 oz. She was right on the money!

[Renarene]

24 hours before my daughter was born they said 8.15. She was 9 exactly at birth.

[snapdragon]

SS? My doctor never offered a weight estimate. From what I've read, I'm glad he didn't!

[lauranicole91]

At 36w3d I was told she was 7lbs 9oz.
She was born exactly one week later and only 6lbs 15oz.
This baby is consistently measuring ahead, but I put no faith in the numbers at this point.

[jesskr3]

With my daughter,They kept say she going to be a small baby, she 6lbs 10 oz. Pretty average I think? This baby they are actually concerned with how tiny she is so, I'll get a couple more ultrasounds. We'll see if she's actually small or if they're being over dramatic.

[Deleted]

Feb 3, 2015 0:01:34 GMT -5 snapdragon said:

SS? My doctor never offered a weight estimate. From what I've read, I'm glad he didn't!

Yeah, ditto here.

[rocksforludo]

I was told 8lbs something and DD was 6lbs15ozs. I can't remember if head size factors into the growth estimates or not, but she had (and still has) a giant head. So maybe that threw it off.

[honeylemon]

Feb 3, 2015 0:01:34 GMT -5 snapdragon said:

SS? My doctor never offered a weight estimate. From what I've read, I'm glad he didn't!

I've never had one either, but I know they are notoriously unreliable.

[Renarene]

Feb 3, 2015 13:43:13 GMT -5 @deziniki said:

Feb 3, 2015 12:41:58 GMT -5 beeorange said:

Is there any other reason for a c/s besides the baby's size? I wouldn't let them try to force you into c-section based solely on U/S measurements. They can be off 2+ lbs in either direction. Plus, there are many women out there that have given birth to huge babies. I think it was @gfj48 that mentioned a coworker or friend had an 11 pound baby vaginally! 

I would at least look at all of your options and research before agreeing to a c-section based on a predicted size. 

It's mostly size from what I understand. There is a slight increased stillbirth risk factor, but that is based on weekly non-stress test results that will begin to be measured possibly next week (although they said they may wait until 29/30 weeks, they hadn't decided). 

I really want to make sure that they take all the factors into account though. While the idea of delivering a 10lb baby vaginally scares me, It scares me more to be cut open if there is any good possibility that a vaginal delivery is safe and possibly for both my body build and baby.

Definitely talk to your doctor, but another reason they may suggest csection is that babies of diabetics don't just tend to be heavier, but have wider shoulders that can lead to shoulder dystocia. I had this with my 9 pound baby. I won't tell you the whole story as not to seem like I'm scaring you into a csection because that's not what I'm trying to do. Lots of people have perfectly healthy vaginal deliveries with diabetes. It's something to discuss with the doc though. I believe 9 years ago I had undiagnosed gestational diabetes. My baby had low blood sugar and needed an IV. Now I am full blown type 2 so I've been struggling with attempting another vaginal birth (this time I will take the pain meds!!) or going with a csection. I wish there was a third option! Haha

[chemmom1]

An ultrasound tech explained to me last pregnancy why growth estimates are so inaccurate, and it has to do with how much of the baby they can see on 1 screen. At your first appointment (6-10 weeks) the baby is so tiny that they can accurately measure it. Once the baby gets larger and larger, they are using a bunch of different measurements to estimate the weight, like femur length, head circumference, arm bone length. So if your baby has short legs but a big head like my son, the measurements will not agree with each other and the estimate will be off.

[soyboy]

My OB felt my belly on my delivery day (at 6am) and said he thought the baby would be 7lbs even and not arrive until after 8pm. Baby was 7lb 3oz and came at 8:15pm

Other than that, I had no other weight estimates done.

[soyboy]

Feb 3, 2015 15:03:12 GMT -5 beeorange said:

Feb 3, 2015 15:00:52 GMT -5 soyboy said:

My OB felt my belly on my delivery day (at 6am) and said he thought the baby would be 7lbs even and not arrive until after 8pm. Baby was 7lb 3oz and came at 8:15pm

Other than that, I had no other weight estimates done.

Woah, that's almost scary how spot on he was. 

I wanted to hit him when he predicted my baby would take 14 hours to make his arrival, but he was right! We will see if he is right this time around!

[honeylemon]

Feb 3, 2015 15:00:52 GMT -5 soyboy said:

My OB felt my belly on my delivery day (at 6am) and said he thought the baby would be 7lbs even and not arrive until after 8pm. Baby was 7lb 3oz and came at 8:15pm

Other than that, I had no other weight estimates done.

I said I've never had a weight estimate but I was thinking just based on ultrasounds.

When I was in labor with Iris, my MW guessed her to be close to 9 lbs. After my water broke and she saw how much fluid I had, she changed her guess to a little over 8 lbs. Iris was 8lbs 2oz.

[saltyh2O]

Accurate for DS within an ounce or so. The last scan at 39wks (and a few days) said 7'5" and he arrived at 40wks+1 day at 7'7"