You should wait till everything is fully healed. This is probably about now if you are 5 weeks post op. I am about to start using this on my reconstructive scars, however I have been using silicone tape for last 4 months. This is extremely good for lessening scars. My plastic Surgeon recommended this. It is by Smith and Nephew and is called cica -care. It is a clear sheet of sticky silicone. I cut this to shape and wore it for 4 months. It is expensive, like about $80, but each sheet lasts about 2 months, and I had bilateral mastectomies with scars 19 and 24cms long. It does seem to work, but now I will start on the bio oil as it is good too. Good luck, love Chris xx