Stretch marks getting worse

Hello

I just turned 17 i have recently started growing more and more insecure about my stretch marks on my butt. I first noticed them when i was about 15 but they were barely noticeable so i didnt mind. Since then they’ve become larger and larger and more apparent. They’re white lines and they make me feel so so so insecure. I think within the last 6 months they have for some reason progressed worse. I am a healthy weight and my weight and height has never really changed at all. Does anyone know why I might be getting these stretch marks? And if there’s anything I can do to reduce/remove them.

Ps- I got the Implanon birth control implant inserted a few months ago… i don’t know if that’s involved.

Thank you :)

Ps- I got the Implanon birth control implant inserted a few months ago… i don’t know if that’s involved.

Thank you :)