Association of Serum Calcium and Vitamin D Levels with Genitourinary Microbiological Shifts in Post-Menopausal Women: A Tertiary Care Center Study

Abstract

Objective: To assess serum calcium and vitamin D levels and identify their relationship with genitourinary microbiological changes in post-menopausal women visiting a tertiary care center.
Study Design: Cross-sectional, observational.
Place and Duration of Study: This study was done at Sadaf Yahya Hospital, a tertiary care center in Daska, Pakistan, between 3rd March 2025 and 29th August 2025.
Material and Methods: There were 217 post-menopausal women (over the age of 45 years) enrolled through non-probability consecutive sampling. Serum vitamin D and Serum calcium levels were measured. The vaginal flora was assessed using high vaginal swabs, followed by Gram staining with Nugent scoring and aerobic and anaerobic culture techniques. Data were analyzed using SPSS version 29. The Spearman's rank test was used to assess the associations. The level of statistical significance is taken at p-value below 0.05.
Results: The mean age of the participants was 54.0 years. 52.1% of the women were found to be deficient in vitamin D, and 68.7% of the women had low calcium levels in their serum. Bacterial vaginosis (Nugent score 7- 10) was identified in 34.1% of participants. A significant association was found between vitamin D status and Nugent score categories (p <0.001). Both vitamin D deficiency (p<0.001) and low calcium levels (p=0.001) were significantly associated with alterations in vaginal flora (as indicated by Nugent score). Serum vitamin D (r=-0.509) and calcium levels (r=-0.199) showed significant negative correlations with Nugent score(p<0.001).
Conclusion: Low serum vitamin D and calcium levels are significantly associated with altered vaginal flora consistent with bacterial vaginosis in post-menopausal women. However, further longitudinal and interventional studies may be done before clinical screening recommendations are made.