Correlation between male age, WHO sperm parameters, DNA fragmentation, chromatin packaging and outcome in assisted reproduction technology

Summary In the human, male ageing results in reproductive hormonal and cellular changes that can influence semen quality (volume, motility, concentration and morphology) and ultimately result in a reduced fertilising capacity and a longer ‘time to pregnancy’ for ageing men as well as an increased risk for miscarriage. This prospective cohort study of 278 patients undergoing a first in vitro fertilisation or intracytoplasmic sperm injection treatment was undertaken to examine whether patient’s age was reflected in sperm motility, concentration, morphology as well as in DNA fragmentation (DFI) and immature chromatin (unprocessed nuclear proteins and/or poorly condensed chromatin) as measured by the sperm chromatin structure assay. This study also investigated the possible influence of male age (after correcting for female age) on their fertilising capacity, on obtaining a pregnancy and a healthy baby at home. Logistic regression analysis did not reveal any male age-related influences on sperm parameters like concentration, motility or morphology. No significant male age-related increase in DFI or immature chromatin was demonstrable for these patients. Elevated male age, after correcting for female age, was not related to lower fertilisation rates or significant decreases in the chance for a healthy baby at home.