Your skin stretches at a level that lotions, oils and creams simply do not penetrate. It stretches from it's deepest depths. So, no oil or cream will prevent them. If you pre disposed to them, you will get them.
Naturally therefore, you see, some women will say - "I used X and Y and didn't get a single mark" and others will say "I didn't use anything and didn't get any" and others will say "I used X Y Z A B and C and got a load of them anyway".
However using lotions and creams will help you to -
- Feel like you are doing something
- Give you a sense of control
- Moisturise your skin to prevent you the discomfort of itchiness
- Be a bonding time with your bump and changing body
So by all means do this. But using these will not link to the appearance of stretch marks.
I got loads during puberty and have concluded I am pre disposed. I haven't gained any new ones or any on my bump yet at 21 weeks, but people get them after the birth even. The three things I've been trying to do from the inside include -
1… drinking tons of water
2...taking a high quality prenatal Omega 3 fish oil supplement
3...gaining weight very gradually
Sometimes I do rub my bump, bum and thighs with an oil I've made - sweet almond, wheat germ, jojoba in equal measures, with neroli and mandarin essential oils in it. It feels wonderful.
Good luck with whatever you choose, closest to natural is best, enjoy the experience, but don't link it to the appearance or non appearance of stretch marks.