How to get rid of stretch marks after a long period of time?

I'm 17 and I've had stretch marks since I was 13, 4 years. Since I'm tan, they're not really that recognizable. But there are some days where you can actually see them, purplish-red, and other days where they look silver/white. It's really weird. Are there certain creams besides coco butter? Or possibly oils? Plus, I might get stretch mark laser removal when I'm 18.