The former Friends actress plays a childless woman approaching middle age who decides to get pregnant by artificial insemination in the new comedy, which opened here this week.
And Aniston's girl-next-door image is being blamed for the lack of bums on cinema seats in the States. Audiences once liked her ordinariness (compared to, say, Angelina Jolie and Jessica Alba) -- even if she has never looked hotter in real life -- and yet for some reason Aniston's screen charm has lost its megawattage, and people aren't going to see her latest film.
Will nudity on screen help the 41-year-old break through to a new audience? Aniston is set to appear topless on screen for the first time and in her most risque role yet, in the upcoming movie Wanderlust.
The low US box office take for The Switch has followed other under-performing movies starring the single actress, including Love Happens and The Bounty Hunter.
The Hollywood Reporter has asked whether Aniston has lost her touch as a leading lady in rom-coms? The magazine points to movies such as The Good Girl and Friends with Money, in which Aniston's characters were less cute and more quirky, and for which the actress got good reviews.
Will Jennifer go for an edgier image to appease Hollywood, and take on rivals such as Scarlett Johansson and Drew Barrymore?
She's going for a sexier image anyway. Wanderlust will be produced by Judd Apatow (Knocked Up) and will see Jennifer play a "free-loving" married woman who lives in a hippie commune, and who takes drugs and sleeps with both men and women.
Celebrity re-inventions are a rough business -- but they can work, with Madonna as the mistress of putting on a new face.
Over her 30-year career, Madonna's ever-changing looks have included an '80s ragamuffin in ripped net leggings, to a '90s space odyssey in a conical bra.
Madge was lady-of-the-manor when she married Guy Ritchie in 2000, and has since been a disco queen (with the release of Confessions on a Dance Floor) and an earth mother with her adoption of David and Mercy.
Unexpected celebrity re-inventions catch us by surprise -- such as controversial comic Russell Brand's calmer public image following the controversy over the obscene phone calls he and Jonathan Ross made to 80-year-old Fawlty Towers actor Andrew Sachs.
Californian stylist Rachel Zoe is credited with helping to soften the image of Hollywood socialite Nicole Richie -- and for bringing the heiress back from looking like she was on the edge.
Out went the ill-fitting, brash ensembles (at one point, party-girl Nicole was looking very thin) and in came flowy boho dresses -- and, indeed, Nicole's personality seems to have followed suit, and she has now settled down with musician Joel Madden, is mum to Harlow and Sparrow, and has her own jewellery business.
Meanwhile, Victoria Beckham has succeeded in getting the edge on her fellow fashionistas in Los Angeles by dropping the chavvy look of hair extensions and belly tops, and embracing old-style glamour. Now, every outing is an occasion for style for the mother-of-three, who trots her boys off to school in six-inch stilettos, holding one of her Birkin bags (she has a collection reportedly worth more than €2m).
Lindsay Lohan has turned to Britney Spears' finance and image guru to get her career back on track. The Mean Girls star -- who is now out of rehab -- has hired celebrity consultant Lou Taylor to get her life in order. Nashville businesswoman Taylor famously helped Spears turn her fortunes around after her breakdown two years ago. And Spears' manager, Larry Rudolph, is also said to want to help 24-year-old star Lohan.
What can Aniston do to re-invent herself? The actress posed for some sexy photos for her new perfume's advertisements in July. The scent, originally named Lolavie, was changed shortly before its launch and is now simply called Jennifer Aniston.
It's fair to say the actress has been sexing up her image since she posed naked (except for that strategically placed tie) on the cover of GQ magazine towards the end of 2008.
Helen Mirren is considered a sex symbol at the age of 65, and Kim Cattrall had it going on as Samantha in Sex and the City while in her forties, so there's no reason why Aniston can't become a sex siren at the age of 41. If the way she currently appears isn't good enough to be a sex symbol in Hollywood, then it will be the mother of all re-inventions.