Genetics plays a bigger role in it more then lotions and creams. So if ur mom has some ull probably get them. Also, dehydrated during pregnancy makes it worse and gaining weight way to fast and too much. Cause in ur belly to stretch. That's where the lotions /creams help but just that help. For dry skin. To keep skin moist. This is my 3rd pregnancy and I have no stretch marks and I have yet to use lotions or creams. But my mom doesn't have any either so I'm likely to not get any.
It's never to late to try! I use organic coconut oil you can get it at any grocery store probably sounds weird but it truly is the best moisturizer i've ever used hydrates the skin well an doesn't leave it oily! But they say if your mom got them and your moms mom an so on then your likely to as well...
It won't hurt to try. But it has other factors too. Genetics and if you are drinking a Ton of water
It is different for everyone. I started using oils and creams the second I found out I was pregnant. I started getting strech marks around 29 weeks.. I still use the creams and oils a few times a day even though I have strech marks. Maybe they will lighten or be less noticable? Good luck!