United Brachial Plexus Network, Inc.

Actually, it is the 18-week ultrasound that is the most accurate in terms of predicting baby size. Most people think that the later ultrasounds (like 37 weeks) are more accurate, but that is not true.

I have never heard that before, could you explain? I don't see how that affects the later head/abdominal circumferance ratio measurement, especially when there is so much growth in the last half of the pregnancy. And that is before many people's GD kicks in. I've been pregnant 8 times and there is always something new to learn it seems.
thanks,
Jenny

I think that the 18 week sono is more accurate because the baby has enough room in the womb to stretch out and allow for more accurate measurements. Beyond that time, the beby is growing and is more balled up in the womb.
I have 3 children. The first was a preemie and a vaginal birth. The second was a vaginal birth resulting in bpi. The third was a c-section -- no bpi. At first, I really wanted to try another vaginal delivery, but after weighing the risks, I could not take the chance. Another vaginal delivery could have resulted in another bpi -- and along with that, years of therapy, surgeries, etc. A c-section meant a much longer recovery for me from delivery, but nowhere near the lifetime my son will be dealing with his bpi.
Also, someone mentioned that bpi during a vaginal delivery is preventable. I believe that is true in most cases, but not all. According to my research, my OB (who delivered my son with a bpi) performed all the correct maneuvers to dislodge a baby during shoulder dystocia. And after performing all the maneuvers to no avail, he made the decision to pull on my son's head to deliver him, knowing that it might cause a bpi. But also knowing that the decision to perform a c-section at that point in my son's delivery would probably have meant brain damage from oxygen deprivation before the baby could have been surgically delivered. Even though a c-section can be performed in minutes, if time has already been spent trying to deliver the baby vaginally, you don't have minutes left to spare. I had no risk factors before my son's birth to alert my doctor to the need for a c-section. I was not obese, gained about 30 pounds during pregnancy, did not a history of carrying large babies, no gestational diabetes (not even a mild case). I even had high blood pressure which usually results in smaller babies. Go figure.

My OB was willing to monitor me closely and attempt a vaginal delivery at about 36 weeks, but I'm glad that I took the safe route and decided to deliver my third child via c-section.

I was going to ask my doc about my pelvic bones to see how far apart they are. I mean, with the measurement of the circumference of head/abdomen, can't he check out my pelvic bones too and tell me the distance? That seems like a silly question but oh well. Thanks!

I read once a couple of years back that the only true method of doing this is to xray your pelvis. Can't really do that while you are pregnant. PLUS we learned at camp that even if your pelvic outlet is wide enough and round enough, the shoulder can still get stuck. If you really want to do a vaginal birth, you really have to find a practitioner who is absolutely EXPERT at dislodging a stuck shoulder.

Very good, Francine. That is what I must do then. Thank you.

As a side note to all of this serious talk, we get to find out the sex in about 13 days (not that I am counting) and I can't wait (obviously)!!! I had to share the excitement!