Clinical outcomes of preimplantation genetic testing for structural rearrangements in couples with chromosomal inversions: a retrospective analysis

Chromosomal inversion is one of the common types of chromosomal structural rearrangements. For couples with chromosomal inversions, the appropriate recommendations for preimplantation genetic testing (PGT) remain a subject of ongoing debate. This study retrospectively included couples who underwent PGT between January 2019 and December 2024. All included couples were classified into subgroups based on karyotyping analysis: PGT-INV (chromosomal inversion), PGT-PV (chromosomal polymorphic variation), PGT-A (normal karyotype), and PGT-SR (other balanced chromosomal rearrangements). The euploid rate of biopsied blastocysts did not differ significantly among the PGT-INV, PGT-PV, and PGT-A groups (P > 0.05); however, a statistically significant difference was observed between the PGT-SR group and each of the other three groups (P < 0.001). The aneuploidy rate in couples with female inversion was significantly higher than that in couples with male inversion (P = 0.046). Meanwhile, the proportion of aneuploid blastocysts associated with rearrangement was significantly higher in pericentric (38.94%) compared to paracentric inversions (23.60%) (P = 0.022). With the inverted fragment size increased, the proportion of aneuploid blastocysts associated with rearranged chromosomes increased accordingly and exhibited a linear trend (P < 0.05). In conclusion, the overall euploid rate of blastocysts in couples with chromosomal inversion showed no statistically significant difference compared to those with normal karyotype and chromosomal polymorphic variation; however, the carrier gender and the size of the inverted fragment are influencing factors for the abnormality rate associated with homologous rearranged chromosomes. Genetic counseling is strongly recommended for couples carrying chromosomal inversions.