D.K.
My mother-in-law's mom told her to use cocoa butter, she did & had 5 kids, no stretch marks. Mil didn't use it, stretch marks, I started but my husband complained of the smell so I stopped, my skin was a mess by the end of that pregnancy! I started using it with the second pregnancy and the old ones started to look better & better and I told my sweetie to get over it. Cocoa butter is cheap & really works! You can also use Vitamin E oil, you can get it cheaply at Trader Joe's. That works well to moisturize & heal skin.
Good luck & congrats on your baby!
D.