Can I microneedle where I have hair?

I am getting a good response in my hairline with microneedling; however, I now want to take it to the areas I am thinning.  Is it safe to do that?

Assuming that you have miniaturization that you want to try to reverse, yes you can microneedle in areas of miniaturization. If you should accidentally microneedle in normal hair, there will be no problems resulting from such an error.