When I had my last ultrasound before my daughter was born by c-section, the ultrasound said she'd be anywhere between 8 and 9 pounds. My doctor put her hands on my belly and estimated 8 lbs 9 oz...and she was only off by an ounce! My blood sugars were very well-controlled, from 5.5 to 5.9 throughout, so it is possible to have a large baby even if you're in ideal ranges.
The c-section for me was a breeze. I didn't eat anything after midnight the night before, and when I had one low blood sugar in the early morning hours, I drank 8 carbs of apple juice. When I arrived at the hospital, the plan was to have an insulin drip, but somehow wires were crossed, and no one had the drip numbers at hand. So my endo approved me to stay on the pump during the c-section and control everything myself. It was kind of wonderful and scary at the same time.
When I was wheeled into the OR, I suspended my pump. The doctors got started with everything, and it was only half an hour before the incision was made. 50 minutes later, my baby came out with the healthiest set of lungs the nurses had ever heard. She was shown to me for a moment (gorgeous!), then she was whisked away for the testing. My husband stayed with her the entire time to make sure they never gave her formula.
Her blood sugar was on the verge of low when she was born, and it ended up dropping to the high end of low -- to the point that they needed to correct. I was insistent that they not give her formula, so the hospital treated her low with donor milk (my milk took a few days to come in because of the c-section).
As for my blood sugars, they were perfect at 100 mg/dl during the c-section (I got to keep my CGM on as well). Once I was closed up, I was wheeled back to the room, and I immediately began my pump again at my pre-pregnancy numbers (provided by my endo). I never had a point where I did not need any insulin.
I had to drink juice every time I nursed, and I experienced some lows, so I adjusted my basal down over the next few weeks. It took a while to find the perfect ratios, and as the months went by, once I thought I found them, they kept changing -- my body got more efficient at producing milk.
What I wish I had known:
Your baby may need a correction for BG even if your A1c was ideal. I knew that the correction may be necessary, but I didn't stress it to my husband because I thought she wouldn't need any supplementation. He was a little scared that she was in the NICU.
Babies born to type 1s can have large shoulders. Something to do with holding the elevated sugars in the shoulder area, I was told. My daughter looked like a linebacker...but the shoulders fade over time.
C-sections tend to bring on jaundice. I was not expecting jaundice at all and did not know that it's common, even among natural births. It's an annoyance (lots of trips to the doctor, lots of time in a bilirubin blanket), but is easily fixed by a bilirubin blanket or time in a light box.
Your blood sugars will most likely be fine in that short window of time during the c-section. Focus on the baby. I wish now that I hadn't worried so much about my BGs and had focused on the miracle of birth.
Congratulations on your little miracle! Enjoy the birth and every single moment with your brand new baby!!