Some health consequences are obesity
Reaction to the outside environment and or reaction to stimuli.
It increases the blood sugar. You have to make sure your blood sugar is not too low or not too high. If it becomes to high/low your health can become really bad. Yes, diabetes is harmful to your body because it can cause a heart disease, stroke, kidney damage, and nerve damage.
Don't smoke and especially do not drink, (as well as stay away from chemicals, pollution, pesticides) it may cause learning disabilities and abnormalities in the baby.