Hey J.,
I can only tell you that you probably already know they are not preventable and that stretch marks are considered genetic, and that they do not occur with every pregnancy for the same woman.
With that said, there is also no real cure, lotion, etc. that will make them go away. As with diet pills those things that claim to work never do.
I can tell you that after surgeries for scars, some dermatologist will prescribed varying concentrations of Retin-A for scarring.
And this does work. You also must keep the area free from tanning. And then like everything else, time heals. Some people a few months, others a few years.
And by all means try some lotions but be cognizant that improvement you see will likely be the same as if you did nothing at all. Or, contact a dermatologist about scarring. I do hope yours fade soon.
-MB