Check with a dermatologist, the only real way is to use creams against stretch marks, if the marks are still red-ish, then it will be easy to make them go away using special creams for them, but if they already turned white then it will be harder.
I'm not sure if they can be prevented, if you'll go through drastic changes of weight/musculature or if you just have bad skin in general, then you will get them no matter what, but if you use creams for them you can control them and make them fade