The effect of paternal and recipient age on the outcome of ovum donation cycles

To evaluate the role of both paternal and recipient age on pregnancy rates (PR) of ovum donation cycles, and to specifically evaluate the role of paternal age on progression to blastocyst. Historical cohort. Fresh ovum donation cycles performed from January 2005 to December 2010 were used for analysis. 428 cycles were identified, 309 were included. Cycles with donor sperm and day 3 transfers were excluded. PR was calculated based on positive pregnancy test 10 days after embryo transfer. The association between paternal age and PR was assessed using multiple linear regression while controlling for donor age, recipient age and whether preimplantation genetic screening (PGS) was performed. This model was also used to assess the impact of recipient age on PR. Blastulation rate (BR) was calculated as a ratio of total blastocysts per day 3 embryos having ≥ 6 cells. The association between paternal age and the log odds of the BR was assessed using multiple linear regression while adjusting for the same covariates. As paternal age increased, BR decreased, and the rate of decrease became steeper with older donors. Increasing paternal age did not significantly impact PR (P=0.896), even after controlling for all covariates. Interestingly, increasing recipient age did result in decreased PR, and this decrease became steeper with increasing donor age. Increasing paternal age affects embryonic progression to blastocyst; however it does not impact overall IVF success rates with oocyte donors. This is likely due to the availability of ample amount of embryos to choose from in a donor cycles. Paternal age may have a higher impact on success rates in regular IVF cycles where the maternal age is older. Finally, this study shows that recipient age affects pregnancy rates in donor cycles suggesting an additional factor that may decrease success rates with increasing maternal age.