Reproductive outcomes of oocyte donation in patients with uterine Müllerian anomalies.

OBJECTIVE

To evaluate live-birth rates per embryo transfer in patients with uterine Müllerian anomalies (UMAs). Secondary objectives were to compare reproductive outcomes between the normal uterus group, the different UMA types, and UMA subgroups with and without required surgery.

DESIGN

This retrospective study compared two cohorts, one with UMAs and other with normal uteri of our oocyte donation program at 12 Instituto Valenciano De Infertilidad/Reproductive Medicine Associates University affiliated clinics from January 2000 to 2020. The oocyte donation reduces confounding because of differences in embryo quality. The primary outcome was the live-birth rate per embryo transfer. Secondary outcomes included the rates of implantation, clinical pregnancy, miscarriage, and ongoing pregnancy. We calculated odds ratios with 95% confidence intervals.

PATIENTS

Infertile women undergoing oocyte donation with UMAs.

INTERVENTION

None.

MAIN OUTCOME MEASURES

The rates of implantation, clinical pregnancy, miscarriage, ongoing pregnancy, and live birth.

RESULTS

We analyzed 58,337 cycles of oocyte donation: 57,869 patients had no uterine malformation, and 468 women had UMAs. Compared with patients with normal uteri, patients with UMAs had lower rates of live births (36.67% [32.84-40.65] vs. 38.1% [95% confidence intervals {CI}: 37.82-38.42]) and ongoing pregnancy (39.74% [35.93-43.66] vs. 41.5% [41.24-41.83]). The miscarriage rate was higher in patients with UMAs (19.5% [16.55-22.85] vs. 16.6% [16.47-16.92]). Specifically, patients with a unicornuate uterus (n=29) had lower rates of implantation (24.07% [13.49-37.64] vs. 42.85% [95% CI: 42.6-43.09]), pregnancy (41.86% [27.01-57.87] vs. 59.51% [59.22-59.81]), ongoing pregnancy (16.67% [6.97-31.36] vs. 41.54% [41.24-41.83]), and live births (16.67% [6.97-31.36] vs. 38.12% [37.83-38.42]). In addition, patients with a partial septate uterus (n=91) had a higher miscarriage rate (26.50% [18.44-34.89] vs. 16.7% [16.47-16.92]). Compared with the normal uterus group, the live-birth rates were lower in the UMA without surgery group (33.09% [27.59-38.96] vs. 38.12% [37.83-38.42]).

CONCLUSION

Among patients who received embryos derived from donated oocytes, live birth and ongoing pregnancy rates were lower in patients with UMAs compared with patients with normal uteri. A higher miscarriage rate was found in patients with UMAs. Patients with a unicornuate uterus had worse reproductive outcomes. Our results show that the uterus is less competent in patients with UMAs.

TRIAL REGISTRATION

This study was registered at clinicaltrial.gov (NCT04571671).