Cytogenetic Insights into Male Infertility: Comparing ICSI Outcomes in Numerical and Structural Chromosome Abnormalities

Abstract Objective The present study set out with the objective of evaluating the impact of chromosomal abnormalities on semen parameters and assisted reproductive outcomes in infertile men. Furthermore, the study sought to compare the effects of numerical and structural chromosomal aberrations on fertilisation, embryo development, and live birth rates, with emphasis on clinical relevance and miscarriage risk. Methodology This retrospective observational study included male patients who underwent chromosomal karyotype analysis as part of infertility evaluation at the Istanbul In Vitro Fertilization and Women’s Health Center between January 2017 and December 2024. The inclusion criteria stipulated that males must have complete karyotype results, while their partners must have normal karyotypes. Exclusion criteria included males with incomplete karyotypes, partners with abnormal karyotypes, those with missing semen analyses, or with incomplete cytogenetic data. Following the application of these criteria, 94 of the 399 men with abnormal karyotypes were deemed eligible. Participants were categorised into three groups: normal karyotype (n = 100), numerical abnormalities (n = 41), and chromosomal translocations (n = 53). A comparison was made of semen parameters, fertilisation rate, embryo quality, pregnancy, miscarriage rates, and live birth outcomes. Statistical analyses were performed using SPSS, with Holm–Bonferroni correction applied for multiple comparisons. Results The present study found that men exhibiting numerical chromosomal abnormalities demonstrated significantly diminished sperm concentrations and elevated rates of oligozoospermia and azoospermia in comparison with those exhibiting chromosomal translocations and normal karyotypes ( p < 0.001). “Men with structural chromosomal translocations exhibited a substantially elevated miscarriage rate (45.5%), while men with numerical chromosomal abnormalities showed a lower miscarriage rate (11.8%), approaching statistical significance ( p = 0.069). hCG positivity was lowest in the control group (42.5%, p = 0.016). These findings emphasize the importance of cytogenetic evaluation, genetic counseling, and the potential benefit of preimplantation genetic testing (PGT) for embryo selection. Conclusions Numerical chromosomal abnormalities exhibited a strong correlation with impaired spermatogenesis. Importantly, structural chromosomal translocations carry a high risk of miscarriage despite ICSI, underscoring the need for genetic counselling and consideration of preimplantation or prenatal genetic testing. Assisted reproductive outcomes, including fertilization, embryo development, and live birth rates, were otherwise comparable across all groups. The markedly elevated miscarriage risk observed in men with chromosomal translocations represents the most clinically significant finding of this study.