Evaluation of In vitro Vitamin D Supplementation and its Impact on Sperm Quality: A Controlled Experimental Study

Vitamin D, widely recognised for its role in bone health and immune function, has recently garnered significant interest for its potential impact on male reproductive health. Several studies have suggested that adequate Vitamin D levels may be associated with improved sperm quality and, consequently, enhanced male fertility.

The study was conducted to evaluate the effects of different concentrations of Vitamin D on sperm parameters in vitro, including motility, viability, DNA fragmentation index (DFI) and sperm DNA decondensation index.

This is a prospective in vitro study conducted on 100 semen samples, comprising 50 normozoospermic and 50 asthenozoospermic samples.

Sperm samples were incubated with different concentrations of Vitamin D (1.625 × 10^-1 M; 1.625 × 10^-2 M; 1.625 × 10^-3 M to 1.625 × 10^-4 M) for varying durations (5, 15 and 30 min). Following incubation, sperm motility, viability, DFI and sperm DNA decondensation index were assessed using standardised laboratory protocols.

Statistical analysis was performed using SPSS (version 27.0.1) with analysis of variance. Results were expressed as mean ± standard deviation, and P < 0.05 was considered significant.

A significant improvement in sperm motility was observed at a concentration of 1.625 × 10^-3 M in both normozoospermic and asthenozoospermic samples. No significant changes were noted in sperm viability across all tested concentrations. DFI and DNA decondensation index showed statistically significant improvements (P < 0.001) in both groups.

Vitamin D supplementation in vitro demonstrated a positive effect on certain sperm quality parameters, particularly motility and DNA integrity. These findings indicate that Vitamin D could represent a promising approach for enhancing male fertility, although further studies on larger cohorts are warranted to confirm these results and establish clinical protocols.