||There's nothing like a movie baby to rejuvenate a sagging career. Just ask John Travolta, or even Steve Guttenberg...After years of forgettable rom-coms and dramas, Jennifer Lopez isn't taking any chances with The Back-up Plan; she's having twins, which is a pretty cagey first plan, if you think about it...The Bronx bombshell and husband Marc Anthony gave birth to twins two years ago, so J-Lo fans will race to The Back-up Plan to see if art imitates life, right? Except that it isn't art. It's barely a movie. More like a sitcom's season arc played out in 105 minutes...Yet this artificially inhabited baby flick kind of works, most of the time. You simply can't resist those cute dimples, cooing sounds and bright eyes following shiny objects...Yep, that Jennifer Lopez is a charmer...She plays Zoe, a pet shop owner with a lovable handicapped dog on a roll cart, so you know she has a big heart. We meet Zoe when she's being artificially inseminated by a quippy doctor (Robert Klein), in hopes of becoming a single mom. Zoe doesn't need a man but that's what she finds soon after pulling up her drawers...Outside the clinic, she enters a cab at the moment a handsome guy named Stan (Alex O'Loughlin) climbs in the other door. They bicker and split. Later, she sees the guy again, running an organic cheese stand at a farmers market. They banter and flirt...Stan treats Zoe to a candlelit garden dinner of pizza and apparently flammable wine. He shows her his cheese cellar, which gets her hot enough to have sex. Then she tells him she's pregnant and the games of pingpong emotion begin. Stan's ready to go the distance, with second thoughts when the twins diagnosis is revealed...First-time screenwriter Kate Angelo betrays her TV roots with each neatly stacked obstacle to happiness, punctuated with shrilly comedy from Zoe's single mom support group. The scene involving one member's natural childbirth that resembles an exorcism is the most unappealing lunge for laughs I've seen in a while. It's a jarring contrast to the sweet movie The Back-up Plan is in its better moments...Credit for that goes to Lopez, massaging an underwritten role into something fine, and O'Loughlin, who I've never noticed anywhere before but projects promising leading man looks and comic timing. Even stock characters -- Zoe's tirelessly supportive friends and relatives -- get style points for giving jobs to old pros Klein, Linda Lavin (Alice) and "Mr. C" himself, Tom Bosley. Of course, the babies are adorable.