Semen quality of 1346 healthy men, results from the Chongqing area of southwest China.
BACKGROUND
Large studies on semen quality of the general healthy population from China are rare.


METHODS
A cross-sectional study was performed to evaluate the semen quality of 1346 healthy men residing in Chongqing area of southwest China in 2007. The semen parameters were measured and compared with the World Health Organization (WHO) criteria. A linear regression model was used to examine the determinants of semen quality.


RESULTS
The medians were 2.3 ml for semen volume, 77.8 x 10(6) per ml for semen concentration, 167.7 x 10(6) for total sperm count, 33% for sperm rapid progressive motility, 52.6% for sperm progressive motility and 70.9% for total motility. According to WHO criteria, 61.1% of healthy males had at least one semen parameter below normal threshold values. Season and abstinence duration were found to be significantly associated with semen quality (P < 0.001). Age, smoking, alcohol use and BMI had little or no effect on semen parameters.


CONCLUSIONS
A high proportion of healthy males in Chongqing area of southwest China had abnormal semen parameters values according to WHO criteria. The semen parameters in the study population were markedly different from those reported for the other Chinese, USA and European populations. The differences remain unexplained and may be due to demographic characteristics, lifestyle, environmental factors or genetic variation.
Li
Yafei
Y
Department of Epidemiology, College of Preventive Medicine, Third Military Medical University, Chongqing 400038, People's Republic of China.
Lin
Hui
H
Ma
Mingfu
M
Li
Lianbing
L
Cai
Min
M
Zhou
Niya
N
Han
Xue
X
Bao
Huaqiong
H
Huang
Liping
L
Zhu
Caizhong
C
Li
Chuanhai
C
Yang
Hao
H
Rao
Zhonglin
Z
Xiang
Ying
Y
Cui
Zhihong
Z
Ao
Lin
L
Zhou
Ziyuan
Z
Xiong
Hongyan
H
Cao
Jia
J
D000328:Adult; D002681:China; D003430:Cross-Sectional Studies; D005298:Fertility; D006801:Humans; D008297:Male; D012044:Regression Analysis; D012621:Seasons; D012746:Sexual Abstinence; D013076:Sperm Count; D013081:Sperm Motility; D013997:Time Factors