Association of Vitamin D Deficiency With Reproductive Hormone Imbalance in Infertile Indian Females: A Case–Control Study

Abstract

Background: Vitamin D is increasingly recognized as an endocrine modulator of female reproductive physiology. Deficiency of this micronutrient has been implicated in ovulatory dysfunction, altered gonadotropin secretion, and infertility. Objective: To evaluate the relationship between serum vitamin D status and reproductive hormone profile in infertile Indian females compared with age- and BMI-matched fertile controls. Methods: A cross-sectional case–control study was conducted on 100 participants (50 infertile, 50 fertile controls) aged 20–40 years at a tertiary care hospital in Central India. Serum vitamin D, luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol, testosterone, anti-Müllerian hormone (AMH), and progesterone were analyzed using standard ELISA methods. Data were statistically analyzed with one-way ANOVA and Pearson correlation. Results: Infertile females exhibited significantly elevated LH (8.92 ± 3.08 mIU/mL), LH/FSH ratio (1.41 ± 0.42), testosterone (0.87 ± 0.29 ng/mL), and AMH (4.24 ± 1.19 ng/mL), with reduced estradiol (128.6 ± 39.2 pg/mL) and progesterone (7.86 ± 2.41 ng/mL) compared with controls (p < 0.01). Vitamin D deficiency (<20 ng/mL) was significantly associated with higher androgenic markers and BMI, and lower estradiol and progesterone levels. Conclusion: Vitamin D deficiency is prevalent among infertile women and correlates inversely with androgenic markers and positively with ovarian steroidogenesis. These findings support a regulatory role of vitamin D in hypothalamic–pituitary–ovarian axis function and female fertility.