Is there a formula for guessing a babies weight before birth?

Question

I am 36 weeks preganant and scheduled for a cestion in two weeks I know the doc can guess by measuring the belly, but just for fun i'd like to do it too. Does anyone know how or a formula for doing so? Ten points

Answer 1

Well, for my baby I was 2 weeks behind gestational age in my 3rd trimester. The ultrasound showed she was 5lbs 4 days before she was born and she was born 5 lbs, 1.5 oz. (3 weeks early, if she'd been term she'd have been 6 or 6 something, I don't remember) They figured that out with the measurement of the thigh bone length and head circumference. The belly measurement I had gave the same results for being 2 weeks behind. Normally, a belly is measured from pelvic bone to the top of the uterus and is the same length as the number of weeks pregnant you are. So I would guess that if you're 36 weeks and measure 36 inches you are having an average size baby, which I think is 7 pounds if you went to 40 weeks. WebMD or someplace should have the weights for the different gestational ages. I've never heard of anyone doing this themselves, but it's worth a shot and could be fun. =)

Answer 2

Thats a tough question even for the Dr to be honest with you. You can typically have a bit of an idea by how big you and your husband were at birth, as well as if you have any prior children. I know how exciting this time is, as I've been there twice now, wanting to know every little detail about them before they were actually born. I had a actual U/S done a week before my 2nd son was born, and your typical U/S can determin within 2 lbs one way or the other. Mine was off even with an U/S performed one week before induction. Hope this helped and good luck!!!

Answer 3

An ultrasound is the best way to even get an idea. But it was off with my last baby. They said he was 8+ lbs but was only 7lb 2 oz when born. Nothing is 100%.

Answer 4

My doctor was able to tell by looking at the ultrasound, and was really very close. I went to a different doctor for my last mth, and he was able to tell I was having a 9lb+ baby just by feeling my tummy, have no idea how he did that. My girl was born 9.7lbs, so he was right! I was huge as a house though, so it just made sense.

Answer 5

Even through ultrasound, they really don't know. My aunt was told that her baby was 8 pounds - after an excruciating vaginal delivery, they discovered she was 11 pounds.

Answer 6

Subtract Your weight before conception from your current weight, less 10%... try that. I was pretty close with my wife.

Answer 7

your Doctor can tell you there is no way to guess because of your weight gain

Answer 8

no