title: Heavy Metal Level in Human Semen with Different Fertility: a Meta-Analysis.
abstract: There are conflicting reports on the heavy metal levels in human semen with different fertilities. The purpose of this analysis is to merge and analyze the differences of heavy metal lead (Pb), cadmium (Cd), zinc (Zn), and copper (Cu) levels in male semen with normal and low fertilities. All documents in both Chinese and English were collected from the PubMed, Web of Science, and Chinese National Knowledge Infrastructure (CNKI) database from inception date to February 19, 2016. We have used RevMan software (version 5.2) for the meta-analysis and Stata software (version 12.0) for the meta-regression and sensitivity analyses. A total of 20 literatures were included in the study. The results of the meta-analysis indicate a significant difference between fertility with three metal ions (Pb, Cd, Zn) while no significant difference with copper, detailed as follows: (i) 10 studies on the lead concentrations with a standardized mean difference (SMD) = 2.07, 95 %CI (0.97, 3.17), P < 0.01; (ii) 13 studies on the cadmium concentrations with an SMD = 0.75, 95 %CI (0.44, 1.07), P < 0.01; (iii) 8 studies on the concentrations of zinc with an SMD = -0.61, 95 %CI (-1.08, -0.14), P < 0.01; and (iv) 9 studies on the copper concentrations with an SMD = 0.42, 95 %CI (-0.29, 1.13), P = 0.247. The results indicate that the men with low fertility have higher semen Pb and Cd levels and lower semen Zn levels; more studies are needed to indicate the association of the semen copper level with fertility.
authors.affiliation: Department of Toxicology, School of Public Health, Wuhan University, DongHu Road 115, Wuhan, 430071, People's Republic of China.
authors.forename: Jiantao
authors.initials: J
authors.lastname: Sun
authors.affiliation: Department of Toxicology, School of Public Health, Wuhan University, DongHu Road 115, Wuhan, 430071, People's Republic of China.
authors.forename: Guangxia
authors.initials: G
authors.lastname: Yu
authors.affiliation: Department of Toxicology, School of Public Health, Wuhan University, DongHu Road 115, Wuhan, 430071, People's Republic of China.
authors.forename: Yucheng
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Toxicology, School of Public Health, Wuhan University, DongHu Road 115, Wuhan, 430071, People's Republic of China.
authors.forename: Xi
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Toxicology, School of Public Health, Wuhan University, DongHu Road 115, Wuhan, 430071, People's Republic of China.
authors.forename: Chuang
authors.initials: C
authors.lastname: Du
authors.affiliation: Department of Toxicology, School of Public Health, Wuhan University, DongHu Road 115, Wuhan, 430071, People's Republic of China.
authors.forename: Lu
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Toxicology, School of Public Health, Wuhan University, DongHu Road 115, Wuhan, 430071, People's Republic of China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Toxicology, School of Public Health, Wuhan University, DongHu Road 115, Wuhan, 430071, People's Republic of China. wchunhong027@whu.edu.cn.
authors.forename: Chunhong
authors.initials: C
authors.lastname: Wang
mesh_terms: D000328:Adult; D002104:Cadmium / Q000032:analysis; D016022:Case-Control Studies; D003300:Copper / Q000032:analysis; D005298:Fertility / Q000502:physiology*; D006801:Humans; D007854:Lead / Q000032:analysis; D008297:Male; D019216:Metals, Heavy / Q000032:analysis*; D012016:Reference Values; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D012661:Semen / Q000737:chemistry*; D015032:Zinc / Q000032:analysis
chemical_list: D019216:Metals, Heavy; D002104:Cadmium; D007854:Lead; D003300:Copper; D015032:Zinc
keywords: Fertility; Heavy metals; Meta-analysis; Semen