estrogen and chemical castration are only used if your hair loss started before 20 yrs, these are the 1% of males who won't respond to DHT blockers no matter what, I have 8 male relatives who used finasteride/dutasteride and they report massive improvement 2 years in use but after 2 years the DHT builds up in the follicle and the scalp tissues create resistance, at the point nothing works beside hair transplant, chemical castration, on the other hand, is permanent, 10 times more effective and achieve results that are better than hair transplants