Funding for this research was provided by:
Special Foundation for State Basic Research Program of China (2013FY110500; 2013FY110511)
Natural Science Foundation of China Youth (81601343)
National Key Technology Research and Development Program of the Ministry of Science and Technology of China (2012BAI32B02)
Text and Data Mining valid from 2020-04-06
Received: 24 October 2019
Accepted: 18 March 2020
First Online: 6 April 2020
Ethics approval and consent to participate
: The present study was approved by the Ethics Committee of National Research Institute for Family Planning. All participants were informed about this study and signed consent forms before completing the questionnaire, agreeing to donate the sample of semen and a random sample of midstream specimen of urine for the use in the current scientific research.
: Not applicable.
: The authors declare that they have no competing interests.