How to overcome male infertility after 40: Influence of paternal age on fertility.

The recent trend toward delayed parenthood raises major safety concerns because of the adverse effects of aging on couple fertility. Studies have demonstrated that aging clearly affects female fertility, but can also affect male fertility. Although several theories have been proposed, the exact mechanisms responsible for the observed age-related decline in male fertility remain to be elucidated. It has been shown that advanced paternal age (PA) is associated with reduced semen volume as well as, reduced sperm count, motility and morphology. Recent studies have also reported that paternal aging is associated with a significant increase in the prevalence of both genomic and epigenomic sperm defects. In the context of natural and intrauterine insemination (IUI) conception, advanced paternal age has been associated with lower pregnancy rates and increased rates of spontaneous abortion (independent of maternal age). In IVF and oocyte donation programs, a significant decrease in late blastocyst development has been seen in those cycles using spermatozoa of men older than 55. However, no significant relationship between paternal age and IVF or ICSI pregnancy rates has been observed. Although there are no treatments that can fully restore the age-related decline in male fertility, various measures have been shown to optimize male fertility potential. Specific therapies (e.g. varicocelectomy) and lifestyle changes (e.g. dietary antioxidant supplements) may help minimize some of the age-related deleterious effects on spermatogenesis, such as, oxidative stress and endocrine abnormalities.