In 2015, Marvel's Avengers: Age of Ultron received a fair share of criticism for the treatment of Black Widow - but the Marvel Cinematic Universe wasn't the only source of controversy. The Silver Age superhero has a long and storied history, appearing in over 50 years' worth of comic books, television show and supplemental material. Marvel may have decided that Natasha Romanoff's fertility was a key issue during the Avenger' sequel, but the company has made this mistake before.

Written and directed by Joss Whedon, the sequel to 2012's The Avengers was successful at the box office but received mixed-to-positive reviews from critics and audiences alike. Common complaints included an overabundance of jokes and comedic moments, uneven pacing thanks to the introduction of numerous main characters (Ultron, Quicksilver and the Scarlet Witch, Vision, Klaue and Hawkeye's family), and a lengthy runtime (despite the Marvel Creative Committee forcing Whedon to remove key scenes that would've better explained the plot). But the relationship between Natasha Romanoff and Bruce Banner - a pairing that has never appeared in the comics - was singled out as a major concern, primarily due to a controversial scene between the two characters in the second act of the film.

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While hiding at Hawkeye's family home, Banner and Romanoff discuss the possibility of running away and starting a life together. Banner, perhaps terrified that he'll pass on his condition, insists he can never have children, to which Romanoff responds "Neither can I. In the Red Room, where I was trained, where I was raised, they have a graduation ceremony. They sterilize you. It's efficient. One less thing to worry about. The one thing that might matter more than a mission. It makes everything easier, even killing. You still think you're the only monster on the team?" Audiences believed Whedon was referring to her inability to have children as a monstrous trait, and the scene was infamous enough to prompt an explanation from Whedon: "Being rendered infertile made her feel unnatural, made her feel cut off from the natural world. But it was her actions that defined her. Her murdery actions. That's what 'monster' meant."

But Age of Ultron was not the first time the company referenced Black Widow's fertility. In Marvel Knights: Millennial Visions in 2001, various authors imagine stories along with accompanying artwork. For Black Widow, writer Amanda Conner imagines the future of 2017, in which a new Black Widow is cloned from a combination of Spider-Man's DNA and the original Natasha Romanoff by Russian scientists who want to bring back the old USSR. The test subject eventually gives birth to 123 children "...like a true spider", before murdering the scientists responsible.

The one-page summary is inoffensive enough, but it's telling that Whedon decided to revisit the issue of Black Widow's children in his film. The subject of pregnancy among female superheroes seems to appear in Black Widow media more than most superheroes in the Marvel Universe. Marvel appears obsessed with Black Widow's fertility, and this occurred long before Age of Ultron.

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