If you have already decided to go for surgery them it's ok, but you have many other options too which is natural and much better of surgery...
Remember onething natural is natural, i handled this type of cases and I know 40% women's gain weight their body after born a baby and the biggest reason is just not proper rest after delivery,
You just need to start yoga and drink lemon with honey everyday for two months .
Also start drinking one glass of hot water when you get up in morning .
You will get back your shape and you will be happy with your natural shape. Be sure and try to do this.
For yoga I can give you few links where you can get steps .
Best of luck