Are Semen Quality and Male Fertility Changing?

Abstract
Several studies over the past 20 years have suggested that the quality of semen is declining in industrialized countries throughout the world, arousing concern about male fertility in the future. The study reported by Auger et al.1 in this issue of the Journal emphasizes this concern again. It would seem prudent, however, to ask whether sperm counts and male fertility are in fact declining.Unfortunately, the literature on this subject is not based on prospective studies designed to assess changes in semen quality and male fertility among members of the general population. In large part, the data gathered by Auger . . .