Dysmenorrhea and premenstrual syndrome (PMS) both refer to conditions that can affect menstruating women. These conditions, however, occur at different points in the menstrual cycle. PMS is caused by fluctuations in hormone levels five to ten days before the start of menstruation. These hormone fluctuations, in combination with other factors, can cause a variety of symptoms, including irritability, fatigue, mood swings, crying, bloating, and food cravings. Dysmenorrhea refers to the intense pain and cramping many women experience before, during, and after menstruation. PMS is a combination of emotional and physical factors women experience prior to menstruation, while dysmenorrhea is the physical pain and cramping caused by the act of menstruating.