Sperm nullisomy is not associated with routine semen parameters but it negatively impacts on ICSI outcomes

Sperm aneuploidy is a result of mis-segregation during meiosis and correlates with male infertility. Among the types of aneuploidy, nullisomy has been reported to be more prevalent in human spermatozoa than disomy; however, nullisomy is not always assessed by FISH, and its relation with basic semen parameters is almost unknown. To establish an association between nullisomy and semen parameters and pathologies, we evaluated the potential clinical value of semen analysis and assessed the diagnosis of sperm nullisomy. A prospective study including a total of 130 patients and 25 donors aged 30-50 years with a normal karyotype was carried out. Sperm FISH analyses were performed, and basic semen parameters and ART outcome data were collected. There were no associations between sperm nullisomy of chromosomes 13, 15, 18, 21, 22, X and Y and basic semen parameters. The odds of nullisomy of chromosomes 13, 15, 16, 17, 18, 21, 22, X and Y were not related to semen pathologies. However, sperm nullisomy had a negative impact on ART outcomes, with significant decreases in fertilisation, blastocyst, pregnancy and implantation rates after ICSI. Sperm nullisomy diagnoses are not detected in semen analyses and are a possible cause of idiopathic male infertility and unexplained recurrent pregnancy loss.