I Had C Section Delivery Before 3 Months.and I Gain

I had c section delivery before 3 months.and i gain 20 kg after delivery. This is my 4th child. My age is 36 and hight 158cm. Before pregnancy my weight was 54 kg and now i m 68 kg.i m planning to join vlcc slimming program,is this program is suitable for me or plz tell me about the side effects.