A novel exploring what is "human," through a human/humanoid marriage. Probably prior to 1964

Question

I'm looking for novel, written between about 1955 and 1965, touching on what it means to be human. The idea is explored through a human/humanoid marriage, and subsequent pregnancy and murder. I believe it was by a major author and written sometime around the release of "The Bramble Bush" since that novel/movie also dealt with something of the same themes in a more mainstream way.

The humanoids in this book had tails, which was the only outward feature that distinguished them from humans. They were considered to be animals, even though many spacers kept them as local "wives." A retired spacer wants to return home, bringing his (decreed) less-than-human long-term companion with him. This, because she isn't "human," is forbidden by law.

In the course of determining their future, she reveals that she is pregnant by him. He believes that this proves her humanity, but he is yet again refused permission to bring her back to Earth. Eventually he kills his own offspring to provoke a trial; if he's found guilty, she must be human.

Pretty radical, but a thought-provoking read, and I'd like to read it again.

Answer 1

That might be The Lovers by Philip Jose Farmer, first published in 1952. I've not read it, but the time-frame is correct, the plot summary below looks plausible, and there weren't many SF authors tackling that kind of subject in the 1950s.

Escaping the religious tyranny of a 31st-century Earth by a fluke assignment to the planet Ozagen, linguist Hal Yarrow found that the worst of Earth had followed him - Pornsen, his personal Guardian Angel, vigilant for any evidence of sin or wrong thinking. Conditioned by a lifetime of submission, Yarrow would have accepted Pornsen's constant spying as an unpleasant necessity and lost himself in the study of the language of Ozagen's intelligent dominant race, the Wogglebugs... but then, hidden in ancient ruins built by humanoids long vanished from the planet, he found Jeanette, a not-quite-human fugitive. For a Believer like Yarrow, unconsecrated contact with any female was forbidden - and love for an alien was unthinkable. But to Yarrow, in every way that counted, Jeanette was warmly and bountifully human. So Yarrow sought the aid of the amiably tolerant Wogglebugs to keep his harboring of Jeanette a secret - and at the same time concealed from his alien allies Earth's farreaching plans for them and their unexploited planet. Yet there was one secret Yarrow did not know and could not imagine... the very special nature and needs of the woman he loved!