Cameron Diaz has warned cinema-goers her latest film, named after pregnancy manual What To Expect When You're Expecting, is no guide to child-bearing.
The film, which sees Cheryl Cole make her Hollywood acting debut, follows the stories of five interconnected couples experiencing the thrills and surprises of having a baby.
Although it is said to be inspired by the best-selling book of the same name, the endless projectile vomiting and the moment one character sneezes and her baby is delivered suggests this it is not altogether like the original guide.
"We didn't feel like it applied, very scientific the book, right?" Cameron Diaz said about reading What To Expect for research purposes.
Jennifer Lopez, Chace Crawford, Matthew Morrison, Dennis Quaid and Chris Rock also star in the film, which Cheryl Cole is using as a vehicle into Hollywood.
She has a cameo role as a talent show judge, ironically filmed shortly after she was dumped from The X Factor USA.
"It was fun. That's why I did it because it was a bit of fun and it was just me being me, doing a role I'm used to," Cheryl said at the premiere.
Diaz, who plays a pregnant TV fitness guru, says she hopes to have children of her own one day through "me actually giving birth, adopting or having a partner who has a child".
Later this year she turns 40 - but unlike many Hollywood actresses has a positive outlook on reaching the dreaded milestone.
"To me getting older is such a blessing because if you're not getting older you're dead!" she laughs.