Expectations are a funny thing. Take movies, for example. A good trailer can set expectations so high that even if the movie is solid, it ends up being a disappointment because it didn't live up to the tease. On the other hand, a bad trailer can lower expectations so much that even so-so films can be surprisingly entertaining by comparison.

So there's a lot riding on the new trailer for "What to Expect When You're Expecting." But does it deliver more than just babies?

Well, that depends on what exactly you're looking for in an ensemble comedy about the ups and downs of getting knocked up (and down). If you're looking for charmingly low-key baby-centric humor from the likes of Elizabeth Banks, Cameron Diaz (with a British accent?!), Jennifer Lopez, Matthew Morrison, Dennis Quaid and even Chris Rock, then chances are you'll be thrilled with this trailer. If you're looking for something that's not chock full of jokes about puking infants, raging hormones and retaining water, well, we're guessing your expectations are off for this one.

"What to Expect When You're Expecting" is just now entering it's second trimester (that means it's not due until May 11), but if you want the Hollywood equivalent of an ultrasound, here's the new trailer from Yahoo! Movies. And let those expectations soar: