A Prospective Study on Clinical Utility of Preimplantation Genetic Testing for Aneuploidy and Structural Rearrangement Under Advanced Medical Care B in Japan.

PURPOSE: To evaluate the clinical utility of preimplantation genetic testing for aneuploidy and structural rearrangements (PGT-A/SR) under Advanced Medical Care B in Japan.

METHODS

This prospective, single-arm, multicenter benchmarking study included couples with recurrent implantation failure, recurrent pregnancy loss, or structural chromosomal rearrangements who underwent PGT-A/SR and first transfer of a category A/B embryo. The primary endpoint was ongoing pregnancy rate per transfer (oPR) at 12-13 weeks; clinical pregnancy rate (cPR) was prespecified as supportive because the registry benchmark used cPR. Outcomes were compared with age-adjusted national registry thresholds using a one-sample proportion test with a normal approximation.

RESULTS

Of 375 couples, 344 underwent PGT-A/SR and 218 reached first transfer. oPR was 48.6% versus 42.4% (p = 0.064) and did not reach statistical significance; cPR was 57.8% versus 42.4% (p < 0.001). Miscarriage rate was 15.9% versus 23.4% (p = 0.045). In women aged 35-39 and 40-42 years, oPR and cPR exceeded age-adjusted thresholds, whereas no benefit was demonstrated in women aged < 35 years.

CONCLUSIONS

On a per-transfer basis, PGT-A/SR was associated with higher cPR and lower miscarriage rate, particularly in women aged ≥ 35 years. Interpretation is limited by the single-arm design and the mismatch between the study endpoint and the registry comparator.

TRIAL REGISTRATION: This study was registered in the Japan Registry of Clinical Trials (jRCT) (jRCT1052220197).