Snatched

Matt and Aubrey, a young and successful show business couple, are having their first child. Based on a friend's recommendation, they go to the best OBGYN in Los Angeles, Dr. Natalie Barnes. She is gorgeous, fit, and intelligent - but Natalie is not the hero she seems to be. She switches sonograms and lies to Aubrey about her needing bed rest, effectively putting Aubrey out of the picture as she attempts to seduce Matt. (imdb)