Miscarriage history is not associated with embryonic aneuploidy in women under 38 years of age with recurrent pregnancy loss.

PURPOSE: This study aimed to determine whether embryonic aneuploidy rates differ between patients with and without recurrent pregnancy loss (RPL). METHODS: This retrospective cohort study included 103 patients with RPL undergoing 128 preimplantation genetic testing for aneuploidy (PGT-A) cycles and 83 controls undergoing 125 preimplantation genetic testing for monogenic defects (PGT-M) cycles, all aged <38 years. Baseline characteristics, ovarian stimulation parameters, and embryologic data were compared. Miscarriage-number subgroup and age-stratified analyses were performed. A modified Poisson regression model evaluated independent effects of the number of prior miscarriages and age on aneuploidy risk. RESULTS: The RPL group had a significantly higher mean age than that of the control group (33.0 ± 2.9 years vs. 31.2 ± 3.7 years, P < 0.001), as well as a lower antral follicle count, oocyte yield, and number of metaphase II oocytes. No significant difference in embryonic aneuploidy rates was observed between groups, in the overall analysis and after stratification by age. A subgroup analysis according to the number of prior miscarriages also revealed no significant difference between groups. A multivariable analysis revealed that the number of prior miscarriages was not associated with aneuploidy risk (adjusted RR: 0.999, 95% CI 0.984-1.015, P = 0.923), and maternal age exhibited a trend toward increased risk of embryonic aneuploidy but this relationship did not reach statistical significance (adjusted RR: 1.007, 95% CI 1.001-1.013, P = 0.022). CONCLUSION: Among patients with RPL aged <38 years, miscarriage history is not associated with embryonic aneuploidy, suggesting that embryonic chromosomal aneuploidy is not the primary determinant of RPL in this population, warranting cautious use of PGT-A alongside comprehensive etiological evaluation.