It really depends on the type of micro needling - ie. depth, passes technique, and additional infusions such as PRP. Results can be seen in as little as 2 weeks with energy based RF micro needling esp. if combined with PRP. As for home needling with say a 0.25 to .5 mm depth needle, many treatments maybe needed. Dr Davin Lim, Brisbane. Australia.
Microneedling alone requires many many treatments to see an "outcome." this is more prevention and combined with lasers to get better results. I suggest seeing an expert. Best, Dr. Emer.