There are checks that you need to do to make sure that you’re fit enough for the surgery. That depends on your age.
If you’re a young and fit individual, and you don’t smoke, basically we call it ASA1 which means you’re perfectly cleared for anaesthesia. Then you don’t really need to do anything, you don’t even need a blood test.
If you’re above a certain age, then you may need to do some blood tests to make sure that you’re safe for anaesthesia. With regards to the breast, I think it would be good for you to do some basic screening, be it a mammogram or ultrasound before you do the implant. Just to make sure that you don’t have any lumps or any signs of breast cancer.
Even after you have implants in, you need to continue to get regular screenings to make sure that you do not have any breast cancer.