'Well, you know, I just — I was thinkin' that I'd just nip it in the bud. Before it gets worse. 'Cause they were talkin' in health class about how pregnancy can lead to ... an infant.'
It's not giving much away to say that Juno MacGuff does not nip her pregnancy, "in the bud" or otherwise. Instead, after a brief flirtation with abortion, the 16 year-old opts to carry the foetus to term and give the baby up for adoption. Significantly, Juno is not punished for her transgression (except insofar as the pregnancy itself meet be considered a punishment) persons seeking in the entrails of Juno any overt anti-abortion, pro-choice, pro- or anti-sex or other coded messages are in for a serious disappointment.
The movie's eponymous title gives the game away.
Juno is a story about (nearly) a year in the life of a teenage girl named "Juno". It is not an issue movie, or a cautionary tale, or a call to arms. The fact that Juno is about a pregnant 16 year-old girl does not mean it is "about" teenage pregnancy.
At its heart and despite its subject-matter, Juno is a romantic comedy. Where we might once have had Katherine Hepburn as a wise-cracking career-woman in a man's world, we now have Ellen Page as a wise-cracking teenager, who is every bit as independent as Hepburn ever was, if in a very different world.
(Spoilers ahead, but not many; this is a movie whose surprises are worth keeping.)