The effects of advanced paternal age on clinical outcomes in assisted reproductive technology

Female age is well known to interfere with reproductive health. There are currently no guidelines or recommendations for future fathers. However, animal models and a number of findings in humans have shown that fertility can be affected by age of the male partner. In mice, older males produce less offspring and in-vitro experiments show adverse effects on blastocyst development and pregnancy success if males are older than 12 months. A prospective study conducted in healthy European couples revealed that male age dramatically reduces pregnancy success, even after adjusting for woman's age. Fertility was significantly declined if a man was in his late thirties. Although the sperm production machinery has a "ticking biological clock", this does not completely explain a man's failure to father a child. The current project aims to decipher -on a larger scale- the associations between male age and sperm characteristics, early stages of embryo growth, and live birth in a fertility setting.  If our data underscore the impact of male age, this may help push the field to (re)consider the impact of the father on achieving a successful pregnancy. Next, clinical decision-making and preventative public health programs would benefit from a better understanding of the role of men.