User blog comment:B214/Question and Answers 6/@comment-9595671-20160714212150/@comment-9595671-20160715004703

Huh, I could have sworn it was Odin that's in charge of the Valkyries. It does say they especially serve him in the Valkyrie category page.

I guess what I am saying is each species in the series we've seen can or potentially as Ex implies have children who will be partially their species, Valkyries however may be the sole exception because they're gender specific.

If Einherjar are considered the male equivalent in this series, then if a Valkyrie had a son then I think they'd become an Einherjar, but that doesn't seem to be the case.