Associations of semen essential/non-essential elements with the risk of male infertility: A systematic review and meta-analysis.

BACKGROUND

Defective sperm function is the leading cause of male infertility, and epidemiological studies have revealed that various trace elements are linked to declining semen quality. However, differences in study quality and the heterogeneity of findings complicate the interpretation of the clinical significance of essential and non-essential elements in semen, especially ultra-trace elements.

METHODS

Essential and non-essential elements in the semen of male infertility were systematically searched within eight databases (Embase, Cochrane, PubMed, MedLine, Web of Science, Chinese Knowledge Infrastructure (CNKI), China Science and Technology Journal Database, and Wanfang database) up to November 2024.

RESULTS

A total of 38 studies involving 5070 patients (male fertility: 3061 vs. healthy control: 2009) were included. Thirty-eight studies measuring five essential elements (Zinc, Zn; Iron, Fe; Manganese, Mn; Selenium, Se; Copper, Cu) and four non-essential elements (Calcium, Ca; Magnesium, Mg; Lead, Pb; Cadmium, Cd) in the semen of men with infertility were included. Random-effect results indicated that the semen Cu (SMD = 0.505; 95 % CI: 0.246-0.764; P = 0.000) and Cd (SMD = 0.725; 95 % CI: 0.534-0.916; P = 0.000) levels in the male infertility group were higher than those of the control group. No significant differences in male infertility patient cases and healthy controls were found for Zn, Fe, Mn, Se, Ca, Mg, and Pb in semen.

CONCLUSION

Elevations of Cu and Cd in semen were associated with the risk of male infertility. Investigation of essential and non-essential elements in semen may help to understand the pathogenesis of male infertility and could also be useful to plan treatment strategies in the future.