I have three favorite pieces of endocrinology-themed fiction.
The short story "Baster" by Jeffrey Eugenides, was featured on this week's New Yorker Fiction podcast. It is in his collection of short stories Fresh Complaint, to be released this fall. "Baster" was adapted into the movie The Switch with Jason Bateman and Jennifer Aniston, but only the first half of the movie, where Wally obsesses over Kassie's impending insemination and eventually switches his own specimen for her better-looking donor's, is drawn from the story. The rest of the movie, dealing with Wally's growing affection for his neurotic son and his eventual confession, are new.
My absolute favorite piece of endocrinology-related fiction is Middlesex, also by Jeffrey Eugenides.
It tells the story of consanguinous parents of a child born with 5-alpha reductase deficiency, a hormonal disorder in which male children do not make enough of the active male hormone dihydrotestosterone.
The red line is the enzyme defect we're talking about here. Image from Wikipedia.
This causes them to be very feminized at birth, with a micropenis and undescended testicles. They were often raised female before the disorder was well-known. But at the onset of puberty, people with the disorder suddenly and sometimes dramatically get male features. Callie (later Cal) is the narrator, and his gender identity evolves in parallel with the family's experience in immigrating from Asia Minor to Detroit, then to San Francisco. It's fantastic.
Finally, the novel The Amazing Adventures of Kavalier and Klay, by Michael Chabon, has a clever endocrinologic twist at the beginning.
It starts off with one of the main protagonists, Josef Kavalier, escaping to New York from Prague, Czechoslovakia by being concealed inside the coffin of the Golem of Prague, a clay mannequin, by his magic teacher, Kornblum. The giant clay mannequin is clothed in the suit of a giant obtained from a deceased patient of Josef's endocrinologist father. It's the first of several escapes by Joe in the book (first from Nazi Europe, then from poverty, then from Antarctica, then from loneliness). The book concludes with (spoiler alert) Sammy, his best friend and cousin, escaping from life as a closeted homosexual. Haunting book.