Effect of paternal age on assisted reproductive outcomes in ICSI donor cycles

Despite growing evidence suggesting age-related molecular changes in gametes, the impact of paternal age on clinical outcomes during infertility treatments has not been adequately assessed.

This study aims to assess the correlation of paternal age to clinical pregnancy and live birth rates in egg donation cycles undergoing intracytoplasmic sperm injection.

This retrospective cohort study includes 4930 fresh oocyte donation cycles from 3995 couples between April 2005 and February 2020 in a private IVF hospital. Clinical pregnancy and live birth rates were the primary outcome measures. The results were also assessed according to the paternal age groups, donor characteristics, semen parameters, fertilization rate, and quality of the transferred embryos.

The age and body mass index of the donors, oocyte maturation, fertilization rates, and the mean number of transferred embryo quality were comparable on day-3 but not on day-5 embryo transfers between paternal age groups (p > 0.05). Paternal age was found to be negatively correlated to the number of oocytes utilized, normal semen parameters, fertilization, clinical pregnancy, and live birth rates (p < 0.05). In day-5 embryo transfer cycles, only the rate of cycles with normal spermatozoa, number of allocated oocytes, and pregnancy were found to be statistically significant.

Paternal age may influence reproductive outcomes and should be considered during infertility evaluations in intracytoplasmic sperm injection donor cycles. Further research is needed to confirm these findings.