Yes and no. It isn't a half finished transformation, its a half mutated one. The original druids of the pack did have a functional wolf form that worked fine for the most part but it often caused them to lose themself to rage when adopting it. They then tried to fix said problem and ended up screwing it all up, not only mutating their wolf form but also making the rage uncontrollable at all times.
Therefore, my point is that since the first Worgen were originally druids in wolf form (of which there is no sexual differences akin to humanoids) they aren't likely to have them as Worgen either.