BACKGROUND: The paternal role in embryogenesis is much more than providing a haploid genome. The spermatozoa have crucial roles related to embryogenesis' epigenetic regulation, fusion of gametes, and cleavage, which may influence intracytoplasmic sperm injection outcomes. OBJECTIVES: To study whether paternal age, length of ejaculatory abstinence and semen parameters influence the outcomes of intracytoplasmic sperm injection in the oocyte recipients from egg-sharing donation cycles. MATERIALS AND METHODS: This historical cohort study involved 427 oocyte recipient intracytoplasmic sperm injection cycles, from 321 patients undergoing egg-sharing donation cycles from January 2015 to May 2017, in a private in vitro fertilization center. Electronic medical records of donors and recipients intracytoplasmic sperm injection cycles were reviewed. The impact of male age, length of ejaculatory abstinence, and semen parameters on recipients' intracytoplasmic sperm injection outcomes were investigated using general mixed models. Implantation, pregnancy, and live birth rates were the primary outcome measures. RESULTS: Paternal age negatively affected fertilization, day 3 top-quality embryos, day 3 normal embryo cleavage speed, blastocyst formation, high-quality blastocysts, and implantation, and was correlated with diminished pregnancy and live birth rates. Length of ejaculatory abstinence negatively influenced the rates of day 3 top-quality embryos, normal embryo development on day 3, blastocyst development, and implantation. Sperm count positively affected the rates of fertilization, blastocyst development, and implantation. The percentage of progressive sperm motility positively affected day 3 normal embryo development rate and implantation rate. Total motile sperm count positively affected blastocyst development rate and implantation rate. DISCUSSION AND CONCLUSION: Additional tracking of the influence of male characteristics on intracytoplasmic sperm injection outcomes should be stimulated. Paternal age is not manageable, but reducing length of ejaculatory abstinence could be an alternative approach to improve the outcomes of intracytoplasmic sperm injection.
BACKGROUND: The paternal role in embryogenesis is much more than providing a haploid genome. The spermatozoa have crucial roles related to embryogenesis' epigenetic regulation, fusion of gametes, and cleavage, which may influence intracytoplasmic sperm injection outcomes. OBJECTIVES: To study whether paternal age, length of ejaculatory abstinence and semen parameters influence the outcomes of intracytoplasmic sperm injection in the oocyte recipients from egg-sharing donation cycles. MATERIALS AND METHODS: This historical cohort study involved 427 oocyte recipient intracytoplasmic sperm injection cycles, from 321 patients undergoing egg-sharing donation cycles from January 2015 to May 2017, in a private in vitro fertilization center. Electronic medical records of donors and recipients intracytoplasmic sperm injection cycles were reviewed. The impact of male age, length of ejaculatory abstinence, and semen parameters on recipients' intracytoplasmic sperm injection outcomes were investigated using general mixed models. Implantation, pregnancy, and live birth rates were the primary outcome measures. RESULTS: Paternal age negatively affected fertilization, day 3 top-quality embryos, day 3 normal embryo cleavage speed, blastocyst formation, high-quality blastocysts, and implantation, and was correlated with diminished pregnancy and live birth rates. Length of ejaculatory abstinence negatively influenced the rates of day 3 top-quality embryos, normal embryo development on day 3, blastocyst development, and implantation. Sperm count positively affected the rates of fertilization, blastocyst development, and implantation. The percentage of progressive sperm motility positively affected day 3 normal embryo development rate and implantation rate. Total motile sperm count positively affected blastocyst development rate and implantation rate. DISCUSSION AND CONCLUSION: Additional tracking of the influence of male characteristics on intracytoplasmic sperm injection outcomes should be stimulated. Paternal age is not manageable, but reducing length of ejaculatory abstinence could be an alternative approach to improve the outcomes of intracytoplasmic sperm injection.