Paternal age does not affect assisted reproductive outcomes when coupled with young oocytes

Abstract

The objective of this study was to evaluate the effect of male age on both semen parameters and reproductive outcomes in fresh ICSI cycles with donor oocytes. Single center, retrospective cohort study of 5,089 ICSI cycles of infertile couples who elected for egg donation to overcome the female fertility issue. The association of male age with the semen parameters and laboratory outcomes were analysed by Multiple Analysis of Covariance (MANCOVA). For the laboratory outcomes the model was adjusted by semen origin (fresh vs. frozen), egg donor age and egg donor body mass index (BMI). The association of male age with the reproductive outcomes (biochemical pregnancy, ongoing pregnancy and live newborn) were modelled by logistic regression, with the following covariates: egg donor age, egg donor BMI, egg recipient age, egg recipient BMI, semen origin (fresh vs. frozen), transfer day (2 vs. 3), mean quality score of embryos transferred (<8 vs. ≥8), and number of transferred embryos (3 vs. 2 vs. 1). The adjusted odds ratios were calculated by logistic regression. Male age (41.2±6.8 y.o.) was associated with a mean decrease in seminal volume of 0.22 ml every 5 years of age (p<0.001), and with a decrease in motile spermatozoa of 1.18% for every 5 years of age (p<0.001); sperm concentration present a mean increase of 3.1 million sperm/ml (p=0.003). No significant association was found between male age and the mean transferred embryo quality (p=0.07). Male age was neither associated with biochemical (OR 1.007; CI 0.0959-1.057) or ongoing pregnancy rate (OR 0.983; CI 0.935-1.033), nor with newborn rate (OR 0.984; CI 0.936-1.035). While we confirmed the negative impact of age on various seminal parameters, we did not find any influence of paternal age on reproductive outcomes when young oocytes are used for ICSI. Further studies are needed to assess postnatal outcomes of children fathered by older men.