Is there a best timing in the menstrual cycle to do a PRP for hair loss? Do hormones levels have any influence?

I am not aware of any data to show that PRP results are affected by fluctuations in hormone levels or the menstrual cycle. Hormones can have an effect on the hair in general as we know, but these are long-term fluctuations rather than daily changes. PRP can be effective in the right patient. Be sure to see a hair restoration specialist.
All the best,

In  my opinion, PRP can be done at any time during the menstrual cycle. Hormone levels do make a difference, but not short-term bursts. Hair receptors respond more slowly. The protocol for injecting PRP is very important. Find a PRP expert. Ask to see photos.PRP hair md.com

There is no impact of the timing of the menstrual cycle on PRP treatments. The procedure can be performed at any time in the cycle.

While hair growth is certainly under hormonal influences this should not impact the timing of PRP treatment during the menstrual cycle. This is because the normal changes in hormone levels during the cycle are negligible with respect to impact on the hair growth cycle. However, if you are taking exogenous hormones, such as an oral contraceptive, these may potentially impact hair growth. Be sure to find an experienced physician with PRP expertise.