<b>Association of Serum Calcium and Vitamin D Levels with Premenstrual Syndrome in Women from District Sialkot: A Case–Control Study</b>

Background: Premenstrual syndrome (PMS) is a multifactorial condition with physical, emotional, and behavioural manifestations that significantly impair women’s quality of life. Emerging evidence suggests that micronutrient deficiencies, particularly calcium and vitamin D, may play a central role in PMS pathophysiology. Objective: To investigate the association between serum calcium and vitamin D levels and PMS among reproductive-aged women in District Sialkot. Methods: A case–control study was conducted involving 40 women diagnosed with PMS and 40 age-matched controls without PMS. Participants underwent structured symptom assessments and venous blood sampling during the luteal phase. Serum calcium was analyzed using the Ortho-Cresolphthalein Complexone method, while vitamin D was quantified by chemiluminescent immunoassay. Group comparisons were performed with independent t-tests, and odds ratios were calculated to assess risk associations. Results: Mean serum calcium was significantly lower in PMS cases compared to controls (7.04 vs. 9.12 mg/dL, p<0.001), with 100% of PMS participants classified as deficient. Mean vitamin D levels were also markedly reduced (22.07 vs. 36.9 ng/mL, p<0.001), with universal deficiency observed in the PMS group. Both micronutrient deficiencies were inversely correlated with PMS severity. Conclusion: Calcium and vitamin D deficiency are strongly associated with PMS and may serve as modifiable risk factors, emphasizing the need for preventive nutritional screening and supplementation strategies.