Stretch marks happen when your body grows faster than your skin can keep up with. This causes the elastic fibers just under the surface of the skin to break, resulting in stretch marks. I had read and article about to how to prevent the stretch marks. My can has followed the same steps it was very useful for her.
How about Gentle Baby Essential Oil from Young Living? It's supposedly really good for stretch marks as a ton of other things. Can also be used for babies for diaper rash and other maladies so it's definitely worth the price since it multitasks.