Buffalo Bill was on in 1983-4. Besides the China Beach episode 74westy mentioned, in a sitcom called Anything But Love (1989-93), Ann Magnuson’s character had an abortion. She was not the main character and it was not the focus of the episode, and actually, I can’t remember anything but the fact of it. But yeah, that was one, and in a one-hour drama called Nothing Sacred (1997-8), which was set in an inner-city Boston Catholic church, a teenage girl had an abortion and afterwards said to the priest, the main character, “Well, I guess this is it for me and God, huh?” I forget his exact words, but it was to the effect that she could move on and she wasn’t excommunicated* and God didn’t hate her.
Askua
Fairly certain there was an episode of Roseanne where they had to write a character out of the show, and they decided to just have him randomly get abducted by aliens. And the final shot of the episode is literally said guy happily hanging out with two aliens in their space ship, and the guy is never talked about again in the rest of the show.
Starting with that season, tag scenes on Roseanne were non-canon**. Arnie left a note (Dan, trying to decipher it, “Who are the Allens and why are they out of spies?”) claiming to have been abducted by aliens, but it was clear he’d taken off for the same reason he did anything: laziness. Arnie did show up again for one episode in the next season, and the tag scene was again in the alien craft. Only this time, Michael Fishman was also there: “I didn’t get enough lines this week.” Meta.
*Excommunication was shown to be a nuclear threat in an earlier episode, maybe the pilot. Some community hotshot had pledged a large and much-needed amount of money, but kept not paying. Father Kevin called him at his office and threatened to excommunicate him, and the guy coughed up. It was implied that he wasn’t so much worried about hell, but that if he was barred from that church, he’d be exposed as the jerk he really was.
**There was another tag scene with Laurie Metcalf polishing her recently-won Emmy. Roseanne grabs for it, then she and John Goodman chase Metcalf off the set and into the studio! And speaking of Arnie, Tom Arnold is already out there to corner Metcalf. And there was the one with Johnny Galecki and Tiny Tim playing ukuleles, and the one with Scott Hamilton and Glenn Quinn skating on the kitchen floor…Anyway, yeah, Arnie didn’t really get abducted, but it was too good not to use for a tag scene.