Most Helpful Guy
Do we notice them? Probably unless we are not looking at them? If they are on your legs while we are looking at your boobs we might not see them. We may be dense at times, but we are not blind.
The bigger question is do we care? Not really. The only reason that we would care is if they are stretch marks because you currently are fat (not just a little overweight, but obese). If we are looking at you naked or in very sexy/revealing clothing, we are not going to care because we like you despite your few physical flaws. If any guy actually cares, you should probably run.
For me I may notice but generally no more than "oh thats interesting" and the I mentally move on. Its not something that I would really focus on unless there is a deeper underlying condition for them that is a current problem or a future problem (unlikely).
Most Helpful Girl
Honestly I'm riddled with them legs, stomach, hips arms they're bloody everywhere and they make me super self-conscious but I've kinda just gotten used to them now and I know eventually they'll fade in color which makes it a bit better.