Successful pregnancy after preimplantation genetic testing for structural rearrangements in a couple with complex chromosome rearrangement and recurrent spontaneous abortion: a case report.

BACKGROUND: Balanced reciprocal translocations and Robertsonian translocations represent two of the most prevalent structural chromosomal rearrangements and may lead to reproductive challenges, including recurrent spontaneous abortion (RSA). The co-occurrence of both translocation types in a single individual constitutes an exceptionally rare cytogenetic finding with significant clinical implications.

CASE PRESENTATION: We present a 36-year-old female with a history of RSA who was found to harbor a compound chromosomal rearrangement consisting of a balanced reciprocal translocation t(2;5)(q33;p13.3) and a Robertsonian translocation der(13;15)(q10;q10). High-resolution karyotyping confirmed the identical rearrangement pattern in the proband's daughter. The patient underwent intracytoplasmic sperm injection with preimplantation genetic testing for structural rearrangements (PGT-SR). Among seven blastocysts biopsied, only one euploid embryo with normal karyotype was identified and subsequently transferred in a natural cycle, resulting in a successful singleton pregnancy with normal prenatal cytogenetic findings.

DISCUSSION AND CONCLUSION: This case highlights the critical role of accurate cytogenetic diagnosis and the application of PGT-SR in improving reproductive outcomes in patients with complex chromosome rearrangement. It also underscores the importance of chromosomal karyotyping in detecting complex chromosomal rearrangements-not only for individuals with RSA but also for their family members. Individualized reproductive planning and genetic counseling remain pivotal for managing such challenging cases.