The root of the word refers to the Greek word hystera, which refers to the uterus. Hysteria -originally- referred to female sexual dysfunction, but medical quackery resulted in becoming a catch-all diagnosis in women experiencing unidentified symptoms.

Given that the treatment was using vibrators or other mechanisms of inducing orgasm, and given that the culture of the era was that men weren't supposed to desire sex/sex was demeaning to them, and women were supposed to be sex-crazy (the reverse is actually a fairly recent phenomenon - watch older movies and you'll still see traces of these attitudes), I suspect that women were frequently more than a little complicit in that particular bit of quackery.

Freud and other contemporary psychologists started using one of the quack versions of the word to describe emotional issues, and it stuck.