Yes, you might get stretch marks during your teen years, even if you’re slender. Girls don’t usually grow taller after age 14, but their bodies may still be changing from puberty. As our breasts grow, stretch marks often form on them. As our hips widen, we may see stretch marks on our hips and thighs. Wherever growth takes place, stretch marks may occur.
If you want your stretch marks to go away, what you might do is apply lotion to them. A doctor once told me that the most effective lotions have lanolin in them. I recommend you find something similar unless you’re allergic to wool; lanolin is a wool byproduct. However there are plenty of skin lotions to choose from. Find one you like and apply it daily.
All of the stretch marks that I had during my growth years went away a long time ago. My pregnancy stretch marks disappeared within a year of giving birth. So don’t worry. As long as you’re eating right, applying lotion, and taking good care of your body, your stretch marks will most likely disappear with time.
Here’s a website that explains what causes stretch marks from a medical/scientific point of view. But if you’re really worried about your stretch marks, go talk to your doctor. It may be very reassuring.