The People I've Slept With (2009)

The People I've Slept With - a promiscuous woman who finds herself with an unplanned pregnancy and needs to figure out who the baby daddy is...NOW. Angela Yang loves sex. She loves it so much she needs to make baseball cards of her lovers to help her remember where she's been. She doesn't think twice about her lifestyle until she finds out that she's pregnant. Her gay best friend, Gabriel Lugo tells her to "take care of it," but her conservative sister, Juliet persuades Angela to get married to the baby's father and lead a "normal" life like her. Angela listens to her sister, chooses to keep the baby, and goes on a quest to find the identity of the father by any means necessary.

Source: TMDb