Stretch marks are visible lines that can be found on your skin surface. Finally, weight changes can cause stretch mark formation. When you are gain weight rapidly, your skin will over-stretched and thus, leave some marks that looks reddish and will fade overtime to get similar to your skin tone. Recently I answered a similar question here posting a link for you I'm 5 feet 7 inches and weight 75kg. Although I just started to use dermelastic serum I can already see a visible difference in my stretch marks. Conversely, it may get worse.