Effects of Vitamin D3 Supplementation in Male Reproductive Function: A Double-Blinded Randomized Controlled Trial

Vitamin D3 supplementation has been shown to be beneficial in improving male reproductive function in some but not all studies. Hence, the benefits of vitamin D3 supplementation on seminal parameters of male infertility remain inconclusive. The current study aims to evaluate the effect of vitamin D3 supplementation on male reproductive function. A double blinded randomized controlled trial was conducted among 120 infertile men. They were randomly assigned into vitamin D and placebo groups. Vitamin D3 (cholecalciferol) supplementation (2,000 IU) was given orally twice daily, and the placebo group received oral vitamin B complex supplementation twice daily. Basic spermogram parameters and hormonal assays including follicle stimulating hormone, luteinizing hormone, and thyroid hormone profile (free T3, free T4, and thyroid stimulating hormone) were performed before and after intervention. Two-way analysis of variance showed statistically significant difference (P < 0.001) with reference to progressive motility, total motility, sperm volume, and total sperm number. There was no statistical difference in the hormonal assay parameters of follicle stimulating hormone and luteinizing hormone; however, the thyroid profile (free T3) alone showed significance between the groups. The present study revealed the beneficial effect of vitamin D3 oral supplementation on spermogram parameters. However, intake of vitamin D3 did not change the levels of follicle stimulating hormone and luteinizing hormone among subfertile men.