Let us say you lost 40 lbs in 4 months, that is 10 lbs were week (2 lbs per week is healthy.) you lost 10 lbs more than what you should have and combined with lack of exercise of the abdominal muscles led to the elastic skin. When you exercise you lose the fat all over except the abdominal fat since you need to do specific exercise for the underlying abdominal muscles to prevent the skin getting elastic in the belly area. You are good candidate for abdominoplasty
) since it does take away the extra loose skin and tightens it. There is no reason why you cannot have this surgery, as long as you eat healthy and maintain an ideal and healthy weight you will do fine.