Background: Premenstrual Syndrome (PMS) is a condition affecting 62 percent of women of reproductive age in India and it’s most prevalent in low socioeconomically background individual. It is characterized by a range of emotional, physical, and behavioral symptoms occurring in the Luteal phase of the menstrual cycle. Symptoms include mood swings, bloating, fatigue, irritability, and depression, significantly impacting daily life. Despite its prevalence, the etiology and pathophysiology of PMS remain poorly understood. Aim: This study aims to investigate the variations in WBC, Platelet and CRP between normal and PMS-affected women in Luteal phases of the menstrual cycle, thereby shedding light on the physiological underpinnings of PMS.