Looking for a story

The story is Science Fiction dealing with gender change brought on by some sort of ray gun. I thought that Anon Alsop had written it but I seem to be wrong. The ray gun not only changes a male to a female but makes her pregnant.

An officer on a military space ship is transformed by another officer's daughter who is jealous and vengeful of him. He, now a she, arrives on a distant planet, buck naked. She eventually makes some crude clothing from animal furs and has the baby. She lives in a crude cave.

Eventually someone arrives intent upon rescuing her but his plan falls apart. They live out their lives there and go to live with Indians....