Due to the dynamic changes in the concentration of sex hormones during the menstrual cycle, a large number of women experience at least some sort of physical and / or psychological symptoms a few days before the onset of bleeding. Also, the increasing use of oral hormonal contraception for reproductive and many other non-contraceptive reasons, has prompted scientists to study and analyze the mechanisms by which natural and synthetic sex hormones affect mood and emotional state. The aim of this paper is to provide an overview of previous findings on the influence of exogenous sex hormones, with an emphasis on combined oral contraceptives (COCs) on processes in the central nervous system that either improve or worsen mood among healthy women and women with premenstrual mood disorders (PMS and PMDD). The paper begins with a brief overview of the central effects of estrogen, progesterone and neurosteroids. Furthermore, that is followed by the presentation of the results of numerous studies, which compare healthy and affected women and which serve as a basis for the theories on the mechanisms of premenstrual mood disorders. The last chapter describes the effects of COCs on mood, emphasizing the pharmacological characteristics of COCs and the individual characteristics of each user, which, in combination, affect the improvement or deterioration of mood.