World J Mens Health.  2020 Apr;38(2):164-177. 10.5534/wjmh.190057.

Vitamin D and Male Fertility: An Updated Review

• Cito G
• Cocci A
• Micelli E
• Gabutti A
• Russo GI
• Coccia ME
• Franco G
• Serni S
• Carini M
• Natali A

• KMID: 2471823
• DOI: http://doi.org/10.5534/wjmh.190057

Abstract

To date, the key role of vitamin D in male reproductive system has been suggested, since the expression of vitamin D receptors and metabolizing enzymes was demonstrated in the testis and spermatozoa. Nevertheless, a general consensus about the role of vitamin D in male fertility is still debated. The aim of this review is to provide an updated systematic revision of the current available literature, discussing the experimental and clinical evidence on the role of vitamin D in the regulation of testis hormone production, seminal parameters and male fertility. The consequences of vitamin D deficiency on serum levels of testicular hormones have been analysed by several observational and interventional studies, with controversial results. Equally, the experimental researches not were able to state a certain relationship between vitamin D status and testis hormone production. Possible bias, including age, body mass index, and baseline vitamin D status justified the differences among studies. As well as concerning the effect of vitamin D on semen parameters, most of the studies agreed in the possibility that vitamin D might have a positive effect on human male fertility potential, particularly through better sperm motility. Regarding pregnancy outcomes, normal level of vitamin D seems to be related to better pregnancies. However, all the previous studies displayed a wide heterogeneity in study design, population, methodology, and cut off values used for the evaluation of vitamin D status. Future studies are needed to better clarify the exact role of vitamin D on hormonal and seminal panel in both fertile and infertile men.

Keyword

Male infertility; Reproduction; Semen quality; Vitamin D

MeSH Terms

Bias (Epidemiology)
Body Mass Index
Consensus
Female
Fertility*
Humans
Infertility, Male
Male*
Population Characteristics
Pregnancy
Pregnancy Outcome
Receptors, Calcitriol
Reproduction
Semen
Semen Analysis
Sperm Motility
Spermatozoa
Testicular Hormones
Testis
Vitamin D Deficiency
Vitamin D*
Vitamins*
Receptors, Calcitriol
Testicular Hormones
Vitamin D
Vitamins

Figure

• 

  Fig. 1 Flow chart of the identified study.

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