How accurate are ultrasound weight measurements?

Question

During our 36 week ultrasound, doctor estimated baby's weight to be about 6 lbs, 6 oz right now and high 7s or low 8s for delivery. Typically how accurate are these ultrasound weight estimates? Anyone have them right around there or were they off?

Answer

They are notoriously inaccurate. They can be off by as much as 2 POUNDS in either direction.

Answer

We declined an ultrasound because, from research, we realized how inaccurate they are. We didn't want medical decisions to be made based on it. For instance, them trying to force a c section on me because baby supposedly measures big.

Answer

I was told my daughter would be well over 9lbs. She was 7lbs 11oz.

Answer

They're estimates.

I was told my son would be no more than 7 1/4 pounds and he was 8 lbs 3 oz.

I was told my daughter would be over 9lbs and she was 8lbs 5oz.

Answer

Okay well now I'm nervous because I've been going to a high risk facility because supposedly baby is weighing small and now they've decided to induce me at 37 wks but now I'm like what if he isn't small and I get induce and then have to get a c section 🤔😫😱

Answer

Also, typically these ultrasounds are done at 36 weeks.. If you go to term at 40, you can add just about two pounds to the estimate given, so I say they can be fairly accurate. (+/- 1lb) They aren't done to tell you how big your baby will be, but what baby is weighing at that gestation, so go from there.

Answer

Had an ultrasound at 36 weeks. They estimated 6lbs 12oz. Baby was born the next night weighing 6lbs 11oz. So pretty accurate.

Answer

Told me that my first would be over 8 pounds. She was 6 pounds 11 Oz full term.

Answer

My last ultrasound where they estimated his weight they put him at 6 pounds 12 oz. they say to plus or minus a pound to get an idea. I'm not sure how accurate mine is though since he's currently measuring at 41 weeks by my fundal height and I'll be 39 tomorrow.

Answer

Very inaccurate! I am actually annoyed that the doctor is going by that to determine how I will give birth. I can't give birth to big babies but I have big babies. 2 weeks ago baby was already measuring 5 pounds and he's predicting a 8 pound baby. I am predicting a bigger baby but we will see

How accurate are ultrasound weight measurements?

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