Criteria to Evaluate Patterns of Segmental and Complete Aneuploidies in PGT-A Results Suggestive of an Inherited Balanced Translocation or Inversion

Abstract Objective To define criteria for determining when preimplantation genetic testing for aneuploidy (PGT-A) results are suggestive of a potential balanced chromosomal rearrangement in the egg or sperm source and warrant karyotyping. Design Performance evaluation of criteria developed to assess PGT-A results for patterns of imbalances suggestive of a balanced chromosomal rearrangement in the egg or sperm source. Setting A single PGT-A laboratory and multiple IVF centers. Patient(s) Reproductive couples who underwent routine PGT-A testing. Interventions(s) Karyotyping of reproductive couples for whom patterns of imbalances observed on PGT-A results suggest a balanced chromosomal rearrangement in the egg or sperm source. Main Outcome Measure(s) Correct or incorrect flagging of predicted translocation in either the egg or sperm source, based on chromosome analysis. Result (s): Proposed criteria correctly predicted a balanced reciprocal translocation in 97% of cases (N = 33), a (13;14) Robertsonian translocation in all cases (N = 3), and an inversion in all cases (N = 2). Other criteria evaluated were determined to be ineffective due to relatively low occurrences that met criteria and/or low predictive value. Conclusion (s): Our results show that the proposed criteria are effective for evaluating patterns of imbalances observed on PGT-A results suggestive of a potential chromosomal rearrangement in the egg or sperm source. Our proposed criteria can be employed by clinicians in the IVF setting in combination with a patient’s reproductive history in identifying PGT-A patients who are likely carriers of balanced chromosomal rearrangements.