# What are they? Here is the best definition I found for them ([here](https://www.aad.org/public/cosmetic/scars-stretch-marks/stretch-marks-why-appear)) > A stretch mark is a type of scar that develops when our skin stretches or shrinks quickly. The abrupt change causes the collagen and elastin, which support our skin, to rupture. As the skin heals, stretch marks may appear. # How to prevent/fix them? Bad news, no actual way to eliminate and/or prevent them. But, according to the page above, looks like the only two things that seem to have had a better impact are the ones below, - Hyaluronic acid - Tretinoin (please note this is probably [not a good one to use during pregnancy](https://www.ncbi.nlm.nih.gov/books/NBK582989/#:~:text=Because%20many%20individuals%20have%20used,to%20use%20tretinoin%20in%20pregnancy.)) One of these days, I will update this post to mention whether the above anecdotally works or not.