P-334 Reduced live birth rates following ART in adenomyosis patients: A matched control study

Abstract Study question How does adenomyosis affect live birth rates (LBR) in women undergoing assisted reproductive technology (ART) compared to a matched control population? Summary answer Women with adenomyosis, matched with controls for age, blastocyst count, and top-quality blastocyst count, exhibited reduced LBR following IVF/ICSI treatment. What is known already Adenomyosis, a benign uterine disorder, is believed to hinder implantation due to anatomical, hormonal, and immune disruptions. Its precise impact on live birth rates (LBRs) following ART, however, remains controversial, with studies presenting inconsistent outcomes. It is uncertain whether adenomyosis directly reduces ART success or if confounding factors such as age or embryo quality play a more significant role. Study design, size, duration This observational study included women aged 18-42 years undergoing IVF/ICSI treatments with a freeze-all strategy from 1 January 2018 to 31 December 2022, each having at least one available blastocyst for transfer. The adenomyosis group consisted of patients with a confirmed diagnosis through pelvic magnetic resonance imaging (MRI), interpreted by gynecologic radiologists. The control group included women without adenomyosis, who had idiopathic, tubal, and/or male factor infertility. Participants/materials, setting, methods A total of 285 women with adenomyosis were included. These patients were matched 1:1 with controls based on age, the number of cryopreserved blastocysts, and the number of top-quality blastocysts. The primary outcome was the cumulative LBR per patient following a single oocyte retrieval, with secondary outcomes including clinical pregnancy rate (CPR) and early miscarriage rate (EMR). Both univariate and multivariate analyses were conducted. Main results and the role of chance In this study, 285 women with adenomyosis were matched with 285 controls. The mean age in both groups was 35.4±3.3 and 35.5±3.4 years, respectively, with an average of 3.5±2.5 and 3.6±2.6 cryopreserved blastocysts and 0.4±0.7 and 0.4±0.5 top-quality blastocysts respectively. In the adenomyosis group, MRI revealed internal diffuse adenomyosis in 73.7% of patients, adenomyoma in 3.5%, and external adenomyosis lesions in 46.7%. The cumulative LBR was significantly lower in the adenomyosis group compared to controls (41.4% vs. 51.9%; Odd Ratio 0.65 95%CI[0.47-0.91]; p = 0.012). Similarly, the CPR was reduced in the adenomyosis group (53.3% vs. 63.9%; p = 0.011). No significant difference was found in the EMR. Multivariate analysis, adjusted for confounders such as freeze-all indication, AMH levels, BMI, infertility type, and ART procedure (IVF vs. ICSI), identified adenomyosis as an independent risk factor for reduced LBR (OR 0.7; 95% CI 0.4-0.9). These findings indicate that adenomyosis is associated with lower ART success rates. Limitations, reasons for caution Patients included in this study were from a specialized referral center focusing on the management of endometriosis and adenomyosis, potentially introducing selection bias, as these women may have more severe forms of adenomyosis. Wider implications of the findings For infertile women, it is crucial for practitioners to conduct comprehensive clinical and imaging assessments to detect adenomyosis. Continued research is needed to refine and personalize ART management strategies for patients affected by this condition. Trial registration number No