Effect of focal adenomyosis on pregnancy outcomes: retrospective propensity score matching analysis of 13,186 IVF/ICSI cycles.

RESEARCH QUESTION: What is the impact of focal adenomyosis on IVF/iICSI outcomes, and what is the optimal protocol for these patients?

DESIGN

This retrospective study screened 66,711 first IVF/ICSI cycles and identified 598 women with focal adenomyosis and 12,588 matched controls with tubal infertility. After 1:3 propensity score matching, 582 patients with focal adenomyosis and 1718 controls were included. Binary logistic regression and generalized estimating equation analyses were performed to analyse pregnancy outcomes.

RESULTS

Focal adenomyosis was not associated with implantation, clinical pregnancy, early miscarriage, late miscarriage or live birth rates, but was associated with higher preterm birth risk in twin pregnancies (adjusted odds ratio [aOR] 2.84, 95% CI 1.14-7.11, P = 0.025). In the focal adenomyosis group, frozen embryo transfer (FET) was associated with lower clinical pregnancy (aOR 0.57, 95% CI 0.36-0.90, P = 0.016) and live birth rates (aOR 0.45, 95% CI 0.27-0.72, P = 0.001), and a higher early miscarriage risk (aOR 3.47, 95% CI 1.23-9.76, P = 0.019) than fresh embryo transfer. Twin pregnancies showed a higher preterm birth risk (aOR 23.54, 95% CI 10.45-53.03, P < 0.001) than singleton pregnancies. Ovarian stimulation protocols and lesion size or number were not associated with pregnancy outcomes.

CONCLUSIONS

Focal adenomyosis increaseded the risk of preterm birth, especially in twin pregnancies. Fresh embryo transfer may be preferable to FET, and elective single fresh embryo transfer should be considered to optimize outcomes. Prospective studies are needed to validate this strategy.