Stretch mark suggestions...

Mandy • I am 34 pregnant w my second. A baby boy. My daughter, who is 4, was born a preemie and thus I'm a NICU Mom.
I have precious stretch marks on my thighs... So I'm not a stranger to what happens....
But this morning I woke up with my first belly stretch mark on the side of me....
I do use oils on myself. 
Can anyone give me any advice on what to use or how to avoid more. 
I am prepared to grow a lot of them but would ultimately like to prevent if possible.
What do you use?