What are risks to the baby if type 1 diabetes in dad?

Higher risk. Having an immediate relative with type 1 dm increases one's risk of developing dm by 10-20 times. Comparing mother and father, if the father has type 1 dm, the risk his children will have it is approx 1 in 10, if mother has it, the risk is lower to 1 in 25. If a brother has it, the risk of another sibling has dm is 1 in 10.
Not at birth. Dad having diabetes does not affect the baby in utero but does increase the risk slightly for the babies future chances of getting diabetes.