It will be important to monitor blood
of your baby to make sure that blood
sugars are returned to normal.
Even if sugars are normal, some women who had gestational diabetes, may later go on in later years to develop either type 1 or type 2.
Diabetes can be well managed with diet (lower carb), exercise, weight management, and medications (if required).
I hope this response is useful to you. Best wishes to you and your wife for the arrival of your second child.