Patient safety is our priority at Lennox Cosmetic Surgery. Because of that, Dr. Lennox requires women to have a body mass index (BMI) below 30 before they can undergo elective breast surgery. According to Canadian guidelines from Health Canada, anyone with a BMI of 30 or higher is considered obese and has a high risk of suffering complications following plastic surgery. A BMI between 25 and 29 is considered overweight.