The Silver-Age of Gender Change Fiction?

Of course it you're talking about fantasy transformations, after people turning into critters, which wins out through the shear number of said happenings found in old myths, and fairy-tales.

The biggest theme of this admittedly small sub-genre, are people changing their sex, not dressing like the other sex, but become such.

There were a few such changes that took place in old myths, and folktales, but it was in the second half of the 20^th century that it really came into its own.

Starting slowly at first with Thorn Smith's novel Turnabout published in 1930 there wasn't much else for 30 or 40 years, other than a bit here, an alien makes Superboy think he's a girl to teach him a lesson, Grandpa and Eddie end up doing some in an episode of the Munsters, a famous cartoon in Mad Magazine by Don Adams, etc.

But slight as it was the theme did grow, so that today I guess we could be said to be in the Silver-Age of the sub-genre, (the Golden-Age being 1995 or so to around 2005 being my guess.)

I mean now Amazon has listings for the subject so you can find novels devoted to it (mind you a lot is straight Kindle items but there is it anyway) and during the time I speculate as being the “Golden-Age” of the genre there was hardly a science fiction or fantasy based television series that didn't use it at least once.

While in comic books there were whole series such as Mantis and Fishnet Angel (yes, that's what I said, Fishnet Angel) with the theme.

And don't get me going about Web Comics with the theme!

Now it seems it's just around, another trope to be used by writers and artist.