Living Mammoth Discovered?

The title isn't nearly as newsworthy as it might first appear, but neither is it as non sequitur as you might think...

By the fact that I'm still blogging, you can probably guess my doctor opted not to order a cesarean delivery for my daughter. At least, not yet. After waiting for what seemed like much longer than 48 hours, I finally got results from my OB's office late yesterday. I tested negative for the dreaded preeclampsia, and although I do have plenty of amniotic fluid, they assured me those levels are still well within range. As his nurse relayed the findings to me, I could almost feel my blood pressure dropping... until she concluded with, "but Dr. D says your baby's a mammoth, so he said to let you know that on Monday you guys'll talk about induction."

I made sure she could hear that I was both smiling and completely serious when I replied, "No, we sure won't."

From my first visit, this particular nurse and I have enjoyed an easy rapport  -- to the point that when I called the office to check on my findings, she saw my number on the caller ID and answered, "What, woman? Whatchoo want?"  :) -- so it's for the best that she was the person on the other end of the phone yesterday.

"Girl," she went on in tones of genuine concern, "the sonogram says your baby's over nine pounds!" I laughed. "Honey," I told her, "that's the very same thing they told me about my son, and he was barely eight. Heck, I've seen them be off by more than two pounds." When she offered a conceding grunt, I continued: "...and the fact is, nine pounds didn't used to be considered a 'mammoth' baby before so many women started getting induced early and delivering six- and seven-pounders. If all my tests say she and I are still doing fine, I'd rather go into labor on my own and try to push out an eleven-pound kid than get induced again. You're welcome to tell Dr. D we'll talk about THAT on Monday." 

She laughed. I could almost hear her shaking her head as she told me, "Will do. See you Monday, sweetie."

I'm sure I don't know everything about childbirth that my doctor does, but I do know he belongs to the American College of Obstetricians and Gynecologists (ACOG), and here's what I learned from medical studies they've published:

Ultrasonographic measurements have been studied extensively, with the mean absolute error of sonographically predicted birth weight ranging 6–15%. These estimations can also be significantly less accurate in infants less than 2500 g (5.5lbs) or greater than 4000 g (8.8lbs).^6–10 Direct comparisons of clinical and sonographic estimates of birth weight have found ultrasound techniques to be superior for preterm infants, clinical assessment to be superior for infants between 2500 and 4000 g, and both techniques to have similar accuracy (or inaccuracy) over 4000 g.^11,12

(excerpted from "Prediction of Birth Weight by Ultrasound in the Third Trimester," Obstetrics & Gynecology 2000;95:502-506.)

With elective induction, the cesarean rate was 57%, significantly higher than the 31% rate with spontaneous labor. [...] 

Conclusion: Because elective induction of labor increased the cesarean rate and did not prevent shoulder dystocia, we conclude that mothers with macrosomic fetuses can safely be managed expectantly unless there is a medical indication for induction.

(excerpted from "Elective Induction Versus Spontaneous Labor After Sonographic Diagnosis of Fetal Macrosomia," Obstetrics & Gynecology 1993;81:492-496.)

In plain English: even America's leading [self-appointed] authorities on childbirth have conceded that a) birth weights determined by ultrasound can be off -- way off; and b) that inducing a mother because her baby might be over eight pounds can only guarantee a "significantly higher" chance of cesarean delivery... and nothing more.

I really like my OB as a person -- he's a better listener than I've ever found in a doctor before -- so I have good reason to think he'll hear me out when I go over the facts with him on Monday. Between now and then, I'll be gathering contact information for the important folks at National Geographic. If I am indeed about to give birth to a mammoth, I can pay for her college by selling them exclusive photo and interview rights...