Cytogenetic risks in chromosomally normal infertile men

Purpose of review Infertility is a growing problem that affects a surprisingly high number of couples (15%) of which the causes often remain 'unexplained'. However, more and more genetic causes underlying male infertility are emerging. Recent findings Research has begun to shed light on the causes of previously unexplained male infertility with clear links now established with infertility and meiotic defects in pairing, synapsis and recombination as well as increased levels of sperm aneuploidy. However, many have questioned whether this increase in sperm aneuploidy is observed in conceptuses or live birth; research suggests that this increase in aneuploidy is in fact paralleled in intracytoplasmic sperm injection (ICSI) conceptions. Summary Further research is warranted investigating the relationship between sperm aneuploidy and risk to ICSI conceptuses. Several infertility phenotypes have clearly been identified having a higher risk of sperm aneuploidy and may benefit from sperm aneuploidy screening prior to ICSI. Such screening would ultimately assist couples in deciding on the relative risk of undertaking ICSI and enable them to make informed decisions on whether to proceed with ICSI or to combine it with further screening such as preimplantation genetic diagnosis.