Risk of Infertility Due to Vitamin D Deficiency among Women with Polycystic Ovarian Syndrome.

Polycystic ovary syndrome (PCOS) is a common endocrine disorder and a leading cause of infertility in reproductive-aged women. Emerging evidence suggests that vitamin D deficiency may exacerbate PCOS-related reproductive and metabolic disturbances. This study aimed to assess the prevalence of vitamin D deficiency among infertile women with PCOS and explore its association with subfertility. This cross-sectional study was conducted at the Department of Infertility, Bangladesh Medical University (BMU), from November 2019 to April 2025. Total 155 infertile women aged 18-40 years; diagnosed with PCOS using the revised Rotterdam criteria (2003) were enrolled. Participants with other known causes of infertility were excluded. Data on demographic variables, clinical features, hormonal profile, glucose metabolism and serum 25(OH) vitamin D levels collected and analyzed. The mean age of participants was 28.34±3.5 years, with a mean BMI of 23.46±3.2 kg/m². Primary subfertility was observed in 69.68% (n=108) of cases. Vitamin D deficiency (<20 ng/ml) was present in 47.10% (n=73) and 40.65% (n=63) had insufficient levels (20-29 ng/ml); only 12.26% (n=19) had sufficient vitamin D (>29 ng/ml). The mean HOMA-IR was 1.88, indicating prevalent insulin resistance. Most participants were normoglycemic with a mean HbA1c of 5.42%. A high prevalence of vitamin D deficiency and insufficiency observed among infertile women with PCOS, particularly among those with primary subfertility. Vitamin D status may represent a modifiable factor in the management of PCOS-related infertility.