Student Research Committee, Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran.
Halal Research Center of IRI, FDA, Tehran, Iran.
Int J Surg. 2019 Nov;71:101-109. doi: 10.1016/j.ijsu.2019.09.025. Epub 2019 Sep 24.
A number of studies have examined the association between vitamin D, fertility and semen quality, however, findings have been inconclusive. Herein, we systematically reviewed available observational studies to elucidate the overall relationship between vitamin D, fertility and semen quality in adult population.
PubMed, Cochrane's Library, Science Direct, Scopus, Google Scholar and ISI Web of Science databases were searched until December 2018 for all available studies evaluating the association between vitamin D, fertility and semen quality. The Newcastle-Ottawa Quality Assessment Scale was used to examine the quality of each study.
A total of 18 studies out of 1843 met our inclusion criteria and were included in our systematic review and meta-analysis. Serum 25(OH)D3 was significantly higher in fertile subjects compared to infertile ones (WMD -0.63; 95% CI, -1.06 to -0.21; P = 0.003). Furthermore, there was a significant association between serum 25(OH)D, sperm motility (WMD -5.84; 95% CI, -10.29 to -1.39; P = 0.01) and sperm progressive motility (WMD -5.24; 95% CI, -8.71 to -1.76; P = 0.003).
Our findings add to the existing literature supporting the concept that nutrition, especially vitamin D, plays an important role in men's sexual health. It should be noted that because of significant heterogeneity among the included studies, caution is warranted when interpreting the results. Further well-designed prospective cohort studies and clinical trials are needed for better understanding of the relationship between vitamin D and fertility and its components.
许多研究已经检验了维生素 D、生育能力和精液质量之间的关系，但结果尚无定论。在此，我们系统地回顾了现有的观察性研究，以阐明成年人群中维生素 D、生育能力和精液质量之间的总体关系。
我们在 2018 年 12 月之前，通过 PubMed、Cochrane 图书馆、Science Direct、Scopus、Google Scholar 和 ISI Web of Science 数据库，检索了所有评估维生素 D、生育能力和精液质量之间关系的可用研究。我们使用纽卡斯尔-渥太华质量评估量表来检查每项研究的质量。
在 1843 项研究中，共有 18 项研究符合我们的纳入标准，并纳入了我们的系统综述和荟萃分析。与不育者相比，可育者的血清 25(OH)D3 水平显著更高（WMD-0.63；95%CI-1.06 至-0.21；P=0.003）。此外，血清 25(OH)D 与精子活力（WMD-5.84；95%CI-10.29 至-1.39；P=0.01）和精子前向运动（WMD-5.24；95%CI-8.71 至-1.76；P=0.003）之间存在显著关联。
我们的研究结果进一步支持了这样一种观点，即营养，特别是维生素 D，在男性的生殖健康中起着重要作用。需要注意的是，由于纳入的研究存在显著的异质性，在解释结果时应谨慎。为了更好地理解维生素 D 与生育能力及其成分之间的关系，还需要进一步进行设计良好的前瞻性队列研究和临床试验。
