Just because women tend to be naturally more empathetic than men doesn't mean that men aren't fit to be psychologists. It just means that more women will pursue that profession.
Also, is empathy a function of only gender - would not the surrounding environment, role model, religion, books read, experiences in life and various other countless factors affect if a person develops empathy?
I don't know, but it would follow from common sense that people who are better at X will be more likely to pursue a career where being good at X is beneficial.
> Also, is empathy a function of only gender
Definitely not. Empathy can most certainly be developed.