Some women experience oral contraception (OC) related increase in negative affect/mood. It may suggest that individual difference variables predispose certain women to specific OC-mediated changes in mood or affect. Only a few studies have examined specific individual difference variables that may increase the likelihood of OC-mediated changes in affect. Furthermore, very few of the studies were conducted using the low-dose OCs that are currently in use. The fact that synthetic sex steroids affect brain excitability and neurosteroidogenesis differentially, might be crucial to understand pharmacological causes of mood changes in women undergoing OC.