Premenstrual Syndrome Type 1 (PMS Type 1) is a condition that affects some individuals in the days leading up to their menstrual period. Symptoms may include mood swings, irritability, and physical discomfort such as bloating or breast tenderness. These symptoms typically resolve shortly after menstruation begins. The exact cause of PMS Type 1 is not fully understood, but it is believed to be linked to hormonal changes during the menstrual cycle. Lifestyle factors, such as stress and diet, can also influence the severity of symptoms. Treatment options may include lifestyle modifications, dietary changes, or medications.