By and large, Stranger Things is a pretty tame show. It managed to keep its TV-14 rating for the sum total of its whole run, and while there would occasionally be some grisly imagery, it basically never veered over into poor taste or anything that general audiences might deem too vile. However, the finale episode of Stranger Things’ final season, “The Rightside Up” seemed to include one of the most insane things the show had ever featured, albeit off-screen: it sure looks like the heroes blow up a building full of pregnant women.
A key plot point of the final two seasons of Stranger Things was that all of the children with supernatural abilities, such as Eleven, came from Hawkins Labs, where Dr. Brenner was conducting experiments, infusing pregnant women with the blood of Henry Creel, a.k.a. the man who would become Vecna. Of course, that whole operation went sideways when Eleven first sent Creel to the Abyss and opened the rift that would come to cause so much trouble in Hawkins. However, season 5 establishes that the new antagonist Dr. Kay, as played by Linda Hamilton, is restarting Brenner’s experiments in a lab of her own. But interestingly, Kay’s labs are located in the Upside Down.
In a flashback scene in which Kali details how she nearly escaped from Dr. Kay’s lab, audiences are shown that there is a whole new batch of full-term pregnant women being kept on super-blood IV there, as the government attempts to breed new supernaturally-powered individuals. In the show, this is the last audiences really see of Dr. Kay’s lab, but it is very much still there.
Then, in the finale of the series, the main characters elect to destroy the Upside Down by placing a series of bombs around the exotic matter keeping it stable that will trigger a chain reaction. They do this, blowing up the Upside Down, without anyone ever even acknowledging that the building full of pregnant women is apparently still in there.
Since the finale’s airing, the Duffer Brothers have attempted to clarify this point in subsequent interviews, telling The Wrap, “Just look at what Kay was trying to do with all those pregnant women. All those pregnant women died because that blood did not work. But if that were to work, then you’ve got dozens of children who are going to grow up just like her and that are going to be turned into weapons and abused.”
Like many things in the final season, this feels like a plot point that could have used a bit more clarification and development in the overarching scheme of things. It would have been nice to follow this thread coherently through the show, rather than having to get backfill from interviews after the fact. But alas, for anyone who was worried that the heroes had the blood of numerous pregnant women on their hands during their extended epilogue, fear not, because according to the Duffers, they merely blew up a building full of pregnant women's corpses.