“Baby Mama” is a formulaic romantic-pregnancy movie that smashes together “Knocked Up” and “The Odd Couple” in a predictable fashion.

The most significant thing about this movie is that it confirms the Judd Apatow’s mixture of current trends and events and gross-out humor is now the gold standard to be emulated by other films. Also, it solidifies the “unexpected pregnancy movie” as a bona fide genre by being the first subpar movie of this mold.

Tina Fey (”30 Rock”) stars as Kate, an upward-moving executive in an organic food company that finds herself overwhelmed with maternal desires. When it is revealed that her chances of conceiving are roughly one in a million, and adoption fails to work out for her, she turns to a surrogate mother.

What she gets is Angie (Amy Poehler, “Saturday Night Live), an uneducated, immature woman who lives with her conniving redneck boyfriend Carl (Dax Shepard, “Idiocracy”). When Angie apparently gets pregnant with Kate’s fertilized eggs, and Kate makes herself a large part of her surrogate mother’s life, everything that could go wrong does.

There are approximately three jokes in this movie. There’s “Pregnancy and parenthood are awkward,” “One woman is obsessively clean and the other is a maladjusted slob,” and finally “The supporting characters are wacky!”

The supporting characters probably fair the best of all the comedic devices. Steve Martin is funny for the first time in twelve years as Kate’s hippy boss. Dax Shepard plays an ignorant white-trash nitwit, apparently the only character he knows, but he plays it admirably and invokes a chuckle with almost every appearance.

Tina Fey fights hard to keep this movie afloat. She is the definite bright spot, as the charming, mature, yet slightly na’ve Kate. Her every joke and bright smile makes the plot’s many contrivances almost forgivable.

Make no mistake, writer-director Michael McCullers (writer of the “Austin Powers” movies) made sure that this movie was as contrived as possible. From the beginning, through the overly long and sagging middle all the way to the end, the plot moves forward without logic.

Things happen because they are supposed to happen, not because they make sense. Fey’s Kate falls in love with Rob (Greg Kinnear of “Stuck on You”) not because there is any romantic chemistry between the two, but because they played by two good-looking stars and that’s just what happens in these kinds of movies.

The last 15 minutes are so contrived that it may bring about questions as to the point having just watched the previous 80 minutes of film. The ending wraps a big shiny bow around the movie with a card that says “Everything is okay now!” In the process, Kate’s personal conflict which drove the entire movie is negated, and the audience is just forced to accept it.

While there are a few funny moments and good performances in “Baby Mama,” the whole product fails to stand up on its own. Fans of Tina Fey will gobble up her every movement in this film, but will find little else to love in this less gross Apatow-style misfire.

2 stars out of 5.

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