I'm afraid I don't think there is Anything that will prevent stretch marks :(
Nothing works :(. My first pregnancy I used stretch mark cream 3 X's a day, still got stretch marks. This time around I'm using nothing and I don't have any new stretch marks. Its genetic and sometimes about how much weight you gain or how big your belly gets. Try not to focus on it, they fade after birth.
I'm going to just consider my MANY stretch marks as my road map to motherhood! :)
Typically, you can't avoid stretch marks. Only make them seem lighter after using creams/lotions. If your mother had them while pregnant, your bound to have them (usually)... My mom said she didn't have stretch marks with me.. I'm almost 33 weeks pregnant and haven't had any real new ones yet. The only time I've gotten stretch marks is when I gained a LOT of weight and then lost some. I've gained almost 20 pounds with this pregnancy now. I know that once I have this baby, I'm going to use creams just to lower the brightness of them if I get them... Also, a LITTLE sun on your belly can help with appearance of stretch marks. Just try not to burn.
I'm 32 weeks and don't have any and I'm hoping I don't get any. I put cocoa butter lotion on everyday, but I've always done that, so I really don't do anything different. There really isn't a way to prevent them like the other ladies said.