About the cover

Decreasing semen quality: true or false?



In 1992, Carlsen et al. reviewed 61 heterogeneous observational studies on semen quality published between 1938 and 1991. The review indicated that mean sperm density decreased significantly in the past 50 years. After that, numerous studies suggest a decline in semen quality in some parts of the world. In contrast, other studies have reported no significant change in semen quality. However, the debate regarding semen quality remains ongoing due to the possible effects of race, geographic differences, selected subject population and so on. In this issue, Li Wang et al. found that semen quality showed a tendency to decrease within 7 years (2008–2014) in 5210 healthy Chinese sperm bank donors. For more information, please refer to pages 521–525 by Wang et al for details. (Artwork is provided by Li Wang and Ya-Wen Gao)

Feedback
Editorial board
Subscribe this journal
Submit articles
Most popular articles
Joiu us as a reviewer
Email alerts
Recommend this journal