The comedy and life lessons in "What to Expect When You're Expecting" are not unexpected.

The romantic-comedy, directed by Kirk Jones ("Everybody's Fine," "Nanny McPhee," "Waking Ned Devine"), is based on the best-selling nonfiction self-help book by Heidi Murkoff with a screenplay by Shauna Cross ("Whip It") and Heather Hach ("Freaky Friday," TV's "Legally Blonde: The Musical").Director Kirk Jones juggles the ensemble comedy of five couples that's 10, count 'em, 10 lead roles as best he can. The focus of the screenplay is off. In fact, there is no focus. There are too many lead characters, none of whom is given enough screen time for each story to be told.Cameron Diaz plays Jules, a Reality TV weight-loss show host. Diaz is fine, but the role is not written to show her best comedic skills. Her pregnancy is a surprise to her and her partner Evan (Matthew Morrison), a Reality TV dance show contestant.Jennifer Lopez is Holly, a professional photographer, who, with her partner, Alex (Rodrigo Santoro), choose to adopt an Ethiopian infant. The adoption scenes in Ethiopia seem as though they are from another movie.Elizabeth Banks plays Wendy, a baby breast-feeding advocate, author and baby supplies store owner, who, with her husband Gary (Ben Falcone), faces motherhood with sincerity, believability and humor.Brooklyn Decker is Skyler, the young wife of Dennis Quaid, who is Ramsey, a retired NASCAR race car driver. They are expecting twins. Each plays their part with a mixture of brashness and brashness.Anna Kendrick plays Rosie, who, with her significant other Marco (Chace Crawford), experience the loss of a baby in the first trimester.In peripheral roles as the Dudes Group, who together walk with their baby strollers and baby holders in the park, are Chris Rock, Rob Huebel, Thomas Lennon and Amir Tabai.To add to the star-power traffic jam, two peripheral characters are given screen time: Davis (Joe Manganiello), a buff runner, and Janice (Rebel Wilson), Wendy's assistant.Talk about a population explosion."What to Expect"' is also thrown off balance by the casting of lesser-known and less-dynamic actors in the males leads. This is not necessarily to fault the actors. It's more a structural problem in the screenplay.And, why any woman would subject herself to watching the multiple birthing scenes in "What to Expect" is beyond me. It's said that the worst part of child birth is blessedly forgotten.Here, the movie-goer is reminded about it again, with in-your-face closeups of women's faces in agony. And since in recent decades fathers have been encouraged to be present when his and the mother's baby is born, birthing is often a shared experience. So, if you are a parent or grandparent, you get to share the pain all over again.In "What to Expect," the parallel birthing scenes how to best say this without making a bad pun? tie the various plot lines in a knot.With "What to Expect When You Are Expecting," you more or less know what to expect: a few laughs and life lessons.The movie has several hilarious scenes and some that tug at your heartstrings. "A miracle is happening inside me," says one expectant mother.Unfortunately, "What to Expect" is no miracle.For single persons, the movie could be a cautionary tale. Or, there could be another outcome.We'll see whether there's a spike in the U.S. birth rate in nine months."What To Expect When You're Expecting," MPAA Rated PG-13 (Parents Strongly Cautioned. Some material may be inappropriate for children under 13) for crude and sexual content, thematic elements and language; Genre: Comedy, Drama, Romance; Run time: 1 hr.; 50 min.; Distributed by Lionsgate.Credit Readers Anonymous: "What to Expect When You're Expecting" was filmed on location in Atlanta, Ga.Box Office, May 25: "Men in Black II" opened at No. 1, with $54.5.1 million for the four-day Memorial Day holiday weekend, time-traveling "The Avengers" to No 3, $36.6 million, $513.3 million, four weeks, after three weeks at No. 1.3. "Battleship," $11 million, $44.5 million, two weeks; 4. "The Dictator," $9.2 million, $41.1 million, two weeks; 5. "Dark Shadows," $7.5 million, $62.9 million, three weeks; 6. "Chernobyl Diaries," $9.3 million, opening; 7. "What to Expect When You're Expecting," $7.1 million, $22.1 million, two weeks; 8. "The Best Exotic Marigold Hotel," $6.3 million, $16.6 million, four weeks; 9. "The Hunger Games," $2.3 million, $395.3 million, 10 weeks; 10. "Think Like a Man," $1.4 million, $88.3 million, six weeksUnreel, June 2:"Snow White and the Huntsman," PG-13: In yet another twist on the Grimm Brothers' fairy tale and a very grim one at that a Huntsman (Chris Hemsworth), ordered by the Evil Queen (Charlize Theron) to take Snow White (Kristen Stewart) into the woods to be killed, becomes her protector."Piranha 3DD," R: The prehistoric piranhas show up at a waterpark. Christopher Lloyd, Gary Busey and David Hasselhoff are along for the ride in the comedy-horror film."Battlefield America," PG-13: An underground dance contest is the subject of the musical drama.Two Popcorn Boxes out of Three Popcorn Boxes