| Insulin does not help to build muscle, but it probably makes your blood glucose in a range that makes you feel good enough to exercise. Having high blood glucose makes it difficult to exercise because glucose can't get into the muscle cells to provide you any power to move.
I have read that it's about a one in seventeen chance of your child having type 1 diabetes if the male has it. The weight of the mother (or father) in the case of Type 1 does not matter because we aren't talking about Type 2 diabetes.
However, that 1-in-17 is a shot in the dark.
You might consider enrolling in a TrialNet project to look into the study of using DHA to push back or halt the progression of potential Type 1. DHA (an omega-3) should be a part of your fiance's diet -- use a DHA that is safe for pregnant women (such as Expectra LIPIL). Also use a baby formula with DHA in it and if she's BF, make sure she continues to have a high intake of omega-3 oils.
Omega-3's have been shown to reduce Type 1 from occurring in 57% of kids that have antibodies that are associated with the development of Type 1. You'll of course want to do more research on this by checking out the journals.
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