As for changes in my eating habits, this pregnancy, I will basically try to do the same thing I did last time: Eat at regular meal times and only at other times when my blood sugar is low. Low blood sugars happen surprisingly frequently during pregnancy, with tight control over my blood sugars, so this really shouldn't be too much of a problem. And yet, I become like a little baby when I feel the weakness of even mild hunger! This weakness strikes about 2 hours after eating, whether my blood sugars are low or not. If I can push past it to 3 hours past eating, I can usually make it to the next meal time without hearing too much feedback from my body.
When I was pregnant with my first son, I was under the tutelage of people who assumed that, whenever you are pregnant and hungry, you should eat. This might be true, if I were willing to eat carrots or celery at these times. But instead, I would eat rich foods, thinking, "if I can't do it during pregnancy, when can I?"
In reflection, I think this was actually a bad idea. I gained 50+ pounds with my first son. He was a modest size, but it was hard to lose the weight, and I was very uncomfortable by the end of that pregnancy. I gained a similar amount of weight with my second son, and he was not in any danger of being too small at birth. This was all well and good, but then I noticed that babies tend to get bigger with subsequent pregnancies. Since I knew my doctors would not be too keen on my having a 10 pound baby (even though I wasn't especially worried), I decided I needed to rein it in a bit.
With my third pregnancy, I worked hard, and kept my weight gain to about 35 pounds. Voila! Healthy, 8 lb 5 oz baby, not too big, not too small. So that's what we're shooting for this time, too.