I think it's basically hereditery!

My Mum had none & neither do either of my sisters or myself.

I never did anything with 1st pregnancy, with 2nd I used some small sachets that were in the Bounty bags & if I remembered I rubbed Vitamin E cream after my shower, with this preg when I remember I use one of the various flavoured Body Shop Body Butters!

But I dont think anything actually prevents them, but by maoisturising it certainly cant hurt!