They do, but in my family's and friends experience, they are usually atleast a pound off. I'm not sure when they attempt to see the weight, they haven't for me yet and I'm 31 weeks.
I am in my 27th week and I have been given a weight once. I had a level II u/s and at approx 19 weeks he weighed 11oz. I am supposed to have another at 29 weeks and I hope that they give me another weight. I would like to see the difference. I feel like he is getting huge already, along with me....lol.
I talked to my doctor and he said they would do one for me about 35 weeks, I had a 9 pounder with my first and he doesnt want him to get that big considering they usually end up a half pound bigger that their bro or sis before them. This doesnt always happen but in my family its usually a pound bigger. But I am paying for a 3d on my birthday in a few weeks just because im courious and I will be about 29 weeks then.
Meg
i know for me at the end of my pregnancy they would feel the baby in my bellie and try to guess what it will weigh when it came out.
they were ususally a little off but i liked having an idea.
robin
hy girls, two weeks ago I had an u/s to determine the weight of the baby because they were concerned that the baby was small and it may not gain weight. Theymeasured her three times that day and she weighted 1300 grams at 29 weeks wich they said it is a normal size baby. 1300 grams is equal to 3 lb. From what I know the baby puts a lot of weight in the las few weeks . . .hopes that helps you.
take care
Thank you ladies for your replies! I am 32 weeks and I wanted to know how much she weighed because it seems like my belly is too small to carry a 3 to 4 lb baby.
I have a 2nd ultrasound my 29 week bc my midwife thought my son was going to be a big boy. They measured the baby and got the weight that way. He was a normal 3lbs! I am now 31 weeks and I feel like he weighs more then me at times!!
Uterian Baby weight 
