Analysis of change in sperm quality of Chinese fertile men during 1981-1996
Zhang, S.C.; Wang, H.Y.; Wang, J.D.
Reproduction and contraception 10(1): 33-39
1999
ISSN/ISBN: 1001-7844 PMID: 12295177 Document Number: 284116
This study analyzed the change in sperm quality and male infertility among men in China from 1983 to 1996. Data were collected from 114 published papers for male sperm quality, including 256 set data from 9292 men and 11,726 semen assays from 39 cities and countries. The results of the analysis showed a decrease in the mean concentration of sperm from 103.02 x 106/ml in 1983 to 83.84 x 106/ml in 1996. Sperm motility decreased from 75.11% in 1982 to 67.27% in 1996, and the percentage of sperm with normal morphology was reduced from 85.02% in 1983 to 77.89% in 1996. These results showed a definite negative correlation and its statistical significance. Furthermore, total sperm counts decreased from 355.34 x 106 in 1984 to 262.26 x 106 in 1996, and the mean seminal volume decreased from 3.31 ml in 1981 to 2.97 ml in 1996, both tending to decline but not being statistically significant. Although the sperm quality of fertile men in China is better as compared with reports from other countries for the same period, the speed of decline (coefficient of regression and decrease rate per year) is higher.