While a number of of the show, user AbbreviationsAway500 started a poll on the series' subreddit intending to determine which storyline is the single most controversial of all according to its fanbase. Decisively amassing the most votes of each of the six possible options was  (Kaley Cuoco) becoming pregnant in the series finale despite having earlier told her partner Leonard (Johnny Galecki) that she explicitly wasn't interested in having kids.

Supporting the fact that this storyline is controversial is the thread's top comment, by user , which reads, "I agree it's a stupid storyline, but Penny says at least twice earlier in the series she wants kids eventually." This kicked off a discussion about whether times Penny was offhandedly open about raising kids one day were legitimate or perhaps less serious than her desire to remain childless in later conversations with Leonard.

In another reply, user argued, "They could have avoided all controversy by adding a single line from her anywhere in season 12, 'I said no kids, now I'm not so sure.'" Commenters then pointed out that, lacking such an explanation, the logic behind how she became pregnant makes Leonard look bad — which was surely not the writers' intent.

Some fans floated other contenders for the show's most controversial storyline

In this same Reddit thread, the number two comment, by user , proposes that the most controversial "Big Bang Theory" scene is not one included among the options presented to users in the attached poll. "I may be wrong but id say it's either Amy's behavior towards Wil Wheaton or Howard and the letter he got from his father," they wrote.

Meanwhile, user argued that another Wheaton moment takes the cake, recounting how he recommends Penny break up with Leonard simply because he seems to want to gain the advantage in a game of bowling. "Oh my god, that was just awful! I'm elderly, but I was still shouting 'Bruh!' at the screen," wrote user in response.

The poll option with the second-highest number of votes is Leonard's whirlwind romance with Priya Koothrappali (Aarti Mann), reinforcing the fact that each of the top contenders for the series' most controversial storyline involves either Wheaton or Leonard. However, this option amassed just 222 votes, well behind the poll winner's 422, suggesting that Penny's pregnancy is far and away the consensus pick.