Bio Oil

Suzie • First time pregnancy my husband and I have been trying for a long time so I'm very thankful/nervous about it!
Hey mamas!
I just bought bio oil today. I am 27 weeks -no stretch marks yet just trying to prevent them the best I can!
For anyone who used Bio Oil -did you use it twice a day or once? Is there a different product you would recommend or did you like it? 
Also someone told me retinal is in bio oil which can harm the baby. Or is it safe for me because baby is growing and not in the early developmental stages?