Hi there! So I have had 2 successful pregnancies, the most recent of which was with twins (!!) :) For both pregnancies, I saw my regular OB, my Endo, and I did see a Perinatologist, which handles the high definition sonograms, and they keep a close eye on baby. The Endo will take primary control over you/your diabetes, the OB takes primary control over you (outside of your diabetes, but as a pregnant mama), and the Peri takes control over looking for issues with baby.
The only bg issues I personally had was as the pregnancy progresses, your bg's tend to run higher, because the placenta gives out a hormone that is anti insulin (great -right?? Especially when you have two placentas in there at once! lol) With both pregnancies I was taking 3x my daily insulin by the time I reached the middle of my 3rd trimester. And then after birth, your insulin needs decrease drastically within the first few hours, so you have to lower your insulin intake dramatically otherwise you'll bottom out.
I did wear an insulin pump (and still do) during both of my pregnancies. It made it so much more convenient when I had to make adjustments. And I would say it 100% helped me stay in better control, but everyone is different.
I had an unscheduled c-section the first time. I was induced at 7am one day and 14 hours later, my son wasn't budging, so they took him via c-section. Main reason was because of my diabetes and I hadn't been able to eat since the night before. With my twins, we knew going into it that I would have a c-section. I had no issues either time related to my diabetes and my deliveries.
Hope that helps, but let us know if you need anything else. Thanks! And good luck!! (By the way, when I was diagnosed, I was 17, a senior in high school, and the admitting doctor told me I'd never have children because of my diabetes. Ha! I showed him! lol)