On getting implants?

This came up because me and my mom were talking about how my cousin is self conscious about her body and wanted mine because I don't gain fat. I mentioned that I didn't like mine either and that I was thinking of implants in the future. My mother told me that my body could change in the future and that it will be a waste. thiIs s true? I thought that your body stops changing sexually around 16-18. I've had the same body since middle school so I doubt that it would change in those areas as an adult. She also mentioned that you can die from implants.
On getting implants?
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