This was a surprise. A teen comedy about a high school pregnancy would normally be low on my list of must-sees, but Juno has a broader appeal than the subject matter immediately suggests. It strikes a good balance between the irreverent and funny, and a more reflective element on the theme of motherhood and family. Don't be putt off by that. Thankfully, it doesn't get stuck on syrupy family values, but positively zings with pointy dialogue from beginning to end.

The script is a strong one, with a terrific performance by twenty-year-old Canadian Ellen Page as the sharp-witted, tomboy teen, Juno McGuff, who becomes accidentally preggers and decides to give it away to a yuppie couple.

Page is in every scene almost and always seems comfortable with writer Diablo Cody's crackling lines. Cody's script seems to have nailed high school vernacular whether it be when Juno is joshing with her best friend Leah (Olivia Thirlby), or in the awkward love between Juno and her geeky, fellow outsider boyfriend Bleeker (Michael Cera).

The storyline, essentially about Juno's decision to ensure a good home for the unwanted baby, is not too predictable, but the film would have looked much more ordinary in the hands of a lesser director and cast. Jason Reitman elevates the script with effective non-linear narrative, and stylistic flourishes while getting the most from his cast, largly plucked from TV-land. For instance, I quickly forgot that Allison Janney was not CJ from the West Wing, but Juno's doggie loving mum and that Jason Bateman as adopted dad-to-be of Juno's baby is the sell-out rockstar turned jingles creator, not the dad character from Arrested Development.

The characters are improbably smart - even the pharmacy shopkeeper has a ready quip at Juno's expense. The female characters are more clearly defined - and male characters, such as Juno's dad are impressively in touch with their sensitive side – although that's not surprising for a film about pregnancy and written by a woman. It doesn't matter, and if anything the film benefits from this skewed femme view of the world. Enjoyable from start to finish.