F&S Reports (Sep 2024)
Initially categorized 46,XY embryo transfer ending with 45,X products of conception—a case report and a review of discordant result management
Abstract
Objective: To report a case of an initially categorized euploid male embryo screened using preimplantation genetic testing (PGT) resulting in miscarriage and testing of products of conception consistent with Turner syndrome, and to discuss additional workup and considerations in cases of discrepancy. Design: Case report. Setting: University fertility clinic. Intervention: Frozen single embryo transfer of a euploid male embryo. Patient(s): A couple seeking procreative management for a female partner having a balanced translocation 46,XX,t(14;16)(q21;q21) diagnosed after the couple’s previous child passed because of segmental duplication in chromosomes 14 and 16 and pursued in vitro fertilization treatment for PGT for structural rearrangements. Main Outcome Measure(s): Miscarriage with discordant chromosomal microarray result. Result(s): Couple conceived with the transfer of a euploid male embryo. After the initial confirmation of pregnancy, repeat imaging indicated a missed abortion. Dilation and curettage were performed, and the products of conception were sent for chromosomal microarray. Results indicated Turner syndrome (45,X). Follow-up short tandem repeat analysis confirmed the products of conception were from the tested embryo. After reevaluation of the data, copy number variations below the reporting threshold for the sex chromosomes were observable and compatible with mosaic 45,X/46,XY. Conclusion(s): The limitations of PGT should be kept in mind when counseling patients because of both the sample provided by biopsy, the sequencing platforms and the laboratory pipeline for diagnosis. We recommend that patients be counseled about these limitations and offered antenatal and postnatal testing as indicated. When discrepancies are seen after PGT, collaboration with the reference laboratory and additional testing with short tandem repeat analysis should be considered when possible.
