Finding the fit: sperm DNA integrity testing for male infertility
Complementing the medical history and physical examination, the semen analysis has been an essential laboratory test for the evaluation of male fertility for over 50 years. However, the concept that fertility is defined by threshold values of semen parameters is fundamentally flawed (1). At best, the semen analysis suggests that the probability of achieving fertility is lower than normal (2). In addition, the definition of “normal” semen parameters is constantly challenged: witness the five editions of WHO manuals in which fertile semen parameters have been redefined over 36 years (3). Lastly, wide intra-individual variation in semen quality (2), and seasonal (4) and geographic variations (5) further complicate the potential of the semen analysis to predict fertility. So, something better is needed to help us determine male fertility potential.