Clinician-induced (iatrogenic) damage incurred during human infertility treatment: Detrimental effects of sperm selection methods and cryopreservation upon the viability, DNA integrity, and function of human sperm

Human infertility is becoming increasingly prevalent and is now estimated to affect 10% of couples worldwide. Although phenomenal development in assisted reproductive technology (ART) has yielded a powerful and sophisticated discipline with which to combat many types of human infertility, success rates vary markedly and rarely exceed 40%. Mounting evidence suggests that laboratory techniques used routinely in ART may inadvertently impart detrimental effects upon gamete and embryo viability and competence. In this mini-review, we discuss how routine cryopreservation methods, commonly used in ART, may exert iatrogenic (clinician-induced) damage upon sperm structure, DNA integrity, and function. It is recommended that future research programmes aim to refine or replace current cryobiology protocols in order that the efficacy of ART can be optimised accordingly.