Originally Posted by
Melissia
Doesn't work like that. The overwhelming majority of Stormtroopers are trained at the Schola Progenium-- IE, from childhood-- to be Stormtroopers. Maybe a fraction of a percent are forwarded from the Inquisition to the Schola for training and are proven worthy of said training.
Most females in the Schola Progenium-- that is, almost half of the Schola students-- become members of the Adepta Sororitas. Some become Stormtroopers, some become Commissars, some give their loyalty to some other Imperial group (some become priestesses, for example), but because of the influence of the Ecclesiarchy as well as the built-in prejudices of the Schola, most of the end up going to the Sisterhood.