The bump and ultrasound aren't accurate indicators!
You uterus could be a huge ball of water and little baby.
My mom's belly was biggest first my birth (compared to her 2 other kids) and I came out the smallest. I was 5 pounds and 6 oz. Also, the ultrasound had said that I was going to be a large baby(they had predicted 8-9 lbs).

It is completely normal to feel worried though if Doctors are making you feel that way.
Remember that your body most likely won't produce a baby that you can't push out.

Try not to freak out my SIL bump was enormous I had never seen anyone so big and she delivered her daughter 1 week before due date by csection and she said when they cut into her she had so much amniotic fluid that some of it came up and soaked her to her shoulders instead of going down the cut outs in the table. Her daughter was only 8lbs. Unfortunately your first one was large so expect this one to be too. My first one was 8lbs 14oz and he was delivered 5 days early. They told me back at 28 weeks that this one was on track to be 7.5 -8lbs. I have only gained 7lbs and do not think that I am overly large and I have really paid attention to make sure my blood sugar stays in check and what I eat. If your blood sugar spikes it can act like a growth hormone and can cause large babies. Other than that its just going to be the way it is. I had an u/s at 32 weeks and 4days and she was 4lbs 7oz. I just had another one at 36 weeks and 4days and she is at 7lbs 3oz. If she gains her 1/2lb per week until due date she will be lighter than my first by 4 oz if she even makes it to her due date. I asked my u/s tech the accuracy of the machines in our office and she said that they are usually accurate within a lb in either direction, but there are exceptions. I have had so many u/s because of weight issues with the first and I was told if they feel that she is getting too big they will suggest an induction. I may consider it so that I don't have to worry about a csection or to deliver a huge baby. Unfortunately when they are large especially in 10lbs it can possibly cause problems health wise with the baby. Try not to worry, but I am with you on the worry and to tell you the truth you do not look that big. You are carrying all in belly and some of us aren't. I should put a picture of mine on here and you can see mine is more distributed evenly from boobs down. Don't get discouraged your doctor is taking extra precautions with the extra u/s and if they are worried will talk induction. I will be 37 weeks tomorrow and my doctor based on that last u/s isn't considering an induction just yet.

With my first son, the doctors were constantly commenting on how large he was going to be. I had multiple ultrasounds. He was 24 inches and 7pounds 12 ounces. I asked them where my huge baby was when they handed him to me! He was such a skinny guy and at 6 years is still a skinny kid. Just relax. Even if your child is the largest ever, or not so small, you will be fine and the doctors will make sure your delivery is safe. You just might not want to invest too much in the fist 2 sizes of diapers...

I am currently pregnant with my third baby - I am *just barely* starting to show right now (like after a big meal LOL) but with my first 2 my bump was HUGE - I was the one constantly getting questioned by strangers asking if I was having twins, people sharing stories of their friend who has a cousin who's sister thought they were having one baby but there was a twin hiding behind it on the ultrasound etc LMAO - I had exactly ONE baby each time, perfectly average sizes of 7 lbs 13 oz and 7 lbs 8 oz - not huge at all, especially compared to the 37 lbs that I gained with each pregnancy! I just carry huge. There is very little space between my pelvis and my ribcage, baby/uterus goes all out in front and I look like I swallowed a watermelon. Bump size does not indicate baby size one bit or I'd have 10 lb babies at least. LOL (I generally measured about 2 weeks larger than my gestational age, too - meaning at 30 weeks my uterus would measure around 32, etc) Position of the baby, fluid levels, etc can affect those measurements as well as ultrasound measurements.

Ultrasounds are not very accurate past the first trimester - they have a range of +/- up to 2 lbs, sometimes even more. Yes sometimes they are quite accurate but not often enough to cancel out the many many times that they are very 'off'. Keep in mind they are looking at a 2-dimensional picture and trying to guess at a 3-dimensional measurement. It's very difficult to be completely accurate b/c there are factors involved that they can't account for. A good friend of mine was talked into having a c-section b/c they did a third-tri ultrasound and said baby would be 'way too big for her' at least 9 lbs - when they did the c-section they pulled out a nice little 7 lb baby. Don't let ultrasound measurements scare you. Even the ACOG (american college of obstetrics and gynecology) says that 'estimated large baby' is NOT a good reason to induce early or do a c-section, simply b/c it is not completely reliable AND you don't know how mom and baby will move/change during labor until you try it. Baby's head squishes (cone head! LOL) and mom's pelvis moves and separates to make room for baby coming through. It's miraculous! We are built to birth babies and babies are built to be birthed. Don't let any possible size estimations freak you out. :-)

I have a pretty small bump. I am actually measuring behind on my belly measurements, but at my 20wk u/s the dr told me to expect a 8.5lb baby. I had another u/s at 32wks and his weight is 4lbs 2oz. Now I am starting to worry he might be huge even though my belly is small. Belly size doesn't determine the size of baby. I had growth u/s with my DD and they were extremely accurate. Few days before I gave birth they had her measuring 6lb10 and she came out 6lb13. I guess we won't know until the babies start coming!!

I have a pretty small bump. I am actually measuring behind on my belly measurements, but at my 20wk u/s the dr told me to expect a 8.5lb baby. I had another u/s at 32wks and his weight is 4lbs 2oz. Now I am starting to worry he might be huge even though my belly is small. Belly size doesn't determine the size of baby. I had growth u/s with my DD and they were extremely accurate. Few days before I gave birth they had her measuring 6lb10 and she came out 6lb13. I guess we won't know until the babies start coming!!

Giving a birth weight estimate at 20 weeks is RIDICULOUS. First off they ave no idea at that point if you'll deliver at 37 weeks or 42 (both are in full-term range). 5 weeks makes a big difference! Secondly, 4 lbs 2 oz is a perfectly respectable 32 week size. My good friend had her first baby just over 31 weeks and he was 3 lbs 19 oz. Third, they should know that ultrasound estimates are not accurate! Telling you what to 'expect' based on their best guess from a 2 dimensional picture and using it to freak you out is crazy! Sometimes they get it very close, sometimes they are WAY off.