Distribution of semen parameters in Taiwanese men
| Year | Participants | Age (year) | Concentration (106/mL)* | Total motility (%) | Progressive motility (%) | Normal morphology (%) |
| 2001 | 501 | 30.8 (4.2) | 41.9 (2.3) | 66.4 (13.7) | 46.9 (15.3) | 71.8 (13.7) |
| 2002 | 611 | 31.1 (4.5) | 41.8 (2.3) | 65.5 (12.9) | 45.7 (15.2) | 66.5 (16.0) |
| 2003 | 558 | 31.5 (4.3) | 42.5 (2.4) | 64.8 (14.3) | 46.4 (15.6) | 67.3 (16.7) |
| 2004 | 535 | 31.1 (4.4) | 40.6 (2.5) | 65.3 (14.0) | 48.4 (15.4) | 67.9 (15.2) |
| 2005 | 519 | 31.5 (3.9) | 38.3 (2.4) | 65.6 (14.2) | 46.5 (15.4) | 70.7 (13.5) |
| 2006 | 530 | 31.3 (4.0) | 39.1 (2.2) | 64.8 (13.6) | 45.7 (15.4) | 65.7 (13.4) |
| 2007 | 517 | 32.0 (3.8) | 38.6 (2.6) | 66.8 (12.7) | 46.5 (15.1) | 65.8 (13.5) |
| 2008 | 556 | 32.3 (4.2) | 38.6 (2.4) | 64.8 (14.9) | 45.9 (15.9) | 65.8 (14.4) |
| 2009 | 437 | 32.5 (4.4) | 39.3 (2.5) | 64.5 (14.8) | 43.9 (14.4) | 64.0 (14.3) |
| 2010 | 447 | 32.7 (4.0) | 39.8 (2.5) | 64.2 (14.5) | 44.4 (15.6) | 63.7 (14.3) |
| 2011 | 424 | 32.8 (4.2) | 40.3 (2.3) | 65.8 (15.4) | 49.1 (18.0) | 66.3 (14.9) |
| 2012 | 402 | 33.0 (4.5) | 44.3 (2.3) | 64.2 (16.5) | 48.1 (17.6) | 67.8 (16.4) |
| 2013 | 322 | 33.2 (4.1) | 44.1 (2.2) | 66.1 (16.6) | 53.4 (19.7) | 72.1 (13.1) |
| 2014 | 116 | 32.7 (4.4) | 45.9 (2.1) | 64.1 (19.5) | 47.1 (17.0) | 77.0 (12.4) |
| All | 6475 | 31.9 (4.3) | 40.6 (2.4) | 65.3 (14.5) | 46.8 (16.1) | 67.4 (14.9) |
| p for trend | – | – | 0.27 | 0.37 | <0.001 | 0.95 |
Results are presented as the mean (SD) for the age and semen parameters.
*Sperm concentration was log-transformed to achieve normality for data analysis and then geometric mean (SD) were transformed back for presentation.