Juno is undoubtedly a teen comedy, in that it is a comedy that concerns teenaged issues. In this way, it fits into the canon of the "teen comedy." While Diablo Cody's quirky story diverges considerably from the tropes of teen comedies, many of which were established long ago in Hollywood and perhaps peaked in the mid 1980s, it shares many of the qualities that make up a "teen comedy," that is, a film concerning youth culture and issues of adolescence, often with a humorous bent.
In an article for the online journal "Screening the Past," Catherine Driscoll, notes that many film critics attribute the birth of the teen comedy to the end of World War II, the decline of the studio system, and the economic need to create new consumer demographics. She writes, "[Thomas] Doherty claims that the decline of the Hollywood studio system in the 1950s, and related threats to the profitability of cinema, produced a flood of films in which teenagers were central in order to cater to a market newly identified as “teenagers." But Driscoll herself argues that teen comedies existed before this wave, and connects them to the rise of psychoanalysis. She writes, "For Freud, adolescence was not a passage into adult roles for which childhood had been a training ground. Instead, it was a complicated clash between new sexual capacity, already conflicting and often inexpressible fears, ideals, and desires built up and elaborated in childhood, and the new social expectations of immanent adulthood." Thus, in cinematic vernaculars, films began to depict adolescence as a site of misunderstanding, self-discovery, joy, and pain, in equal measure. Surely Juno, with its depiction of the complicated and multifarious experiences of adolescence as encapsulated by the theme of teen pregnancy, reflects this.
In an article for The Atlantic, Garin Pirnia writes about the peak of young adult and early teenaged film fare, the mid-1980s. Pirnis recalls, "This trend [a turn towards more youth-oriented family-friendly fare] peaked [in 1984], which saw a hodgepodge of underperforming cult classics and smash hits such as Back to the Future, The Goonies, Pee-Wee’s Big Adventure, and Clue, as well as a score of teen-angst dramas and comedies such as The Breakfast Club. It was a short-lived crest in artistic innovation and creativity: After 1985, the number of youth-oriented films dwindled each year, leaving the genre almost dead by the end of the decade." In this way, we can perhaps look at Juno as a defining film for its time, the early 2000s, and also a film that is nostalgic for the kind of refreshing but wholesome teen films of the mid-1980s.