Actually that very topic came up once, when I was a hard-core dub. I was relating what happened to an employee at work who had to do jury duty for a murder trial. A husband killed his wife, simple enough, except that when motive came up, you know, jealousy, cheating spouse, etc., the details about the "husband's" sex change operation came into the open. The worst part was that the adult daughter was in attendance during the trial and only found out about it along with everyone else - her "father" had actually been a woman at one time and had had a sex change operation. And .... while a woman, this person had had a baby. Guess who? Right, the daughter. So the daughter finds out that her father is actually her mother, and that her father/mother killed her mother who ended up not really being her mother, but the spouse of her real mother. Talk about convoluted.
Anyhoo, I said "wow, imagine if a couple like that came into the troof!"
The CO said that they'd have to get divorced and revert back to the way they were. "You are as when you were born, either male or female. That's the way Jehovah created you and that's what you are till the day you die."