Presence of adenomyosis at MRI reduces live birth rates in ART cycles for endometriosis

STUDY QUESTION: What is the impact of adenomyosis on the live birth rate (LBR) in women affected by endometriosis women undergoing ART? SUMMARY ANSWER: For women undergoing ART, the presence of adenomyosis at MRI, especially T2 high-signal intensity spots within the myometrium, has a negative impact on the LBR. WHAT IS KNOWN ALREADY: Adenomyosis is a common gynecological disease. The development of imaging techniques for the diagnosis has led to several adenomyosis phenotypes being described, and fertility issues appear to vary according to the characteristics of the lesions. What makes assessment of the impact of adenomyosis on fertility issues even more difficult is its frequent association with endometriosis, which is another known risk factor of infertility. Although data suggest that adenomyosis may worsen the ART prognosis, there is no clear consensus regarding the impact of adenomyosis on ART outcomes in women affected by endometriosis. STUDY DESIGN, SIZE, DURATION: This was an observational study that included phenotyped patients with endometriosis, aged between 18 and 42 years, who underwent IVF/ICSI treatment in a tertiary care center between June 2015 and July 2018. Only women who had undergone a pelvic MRI during the pre-therapeutic ART workup were retained for this study. The MRI data were interpreted by radiologists who had expertise in gynecological MRI. PARTICIPANTS/MATERIALS, SETTING, METHODS: A continuous series of 202 women affected by endometriosis was included. The women were monitored until four ART cycles had been completed, until delivery, or until discontinuation of treatment before the completion of four cycles. The primary outcome was the delivery of at least one live infant after up to four IVF/ICSI cycles. The patient and the MRI characteristics were compared between the women who achieved a live birth versus those who did not. MAIN RESULTS AND THE ROLE OF CHANCE: The patients' mean age was 32.5 ± 3.7 years. Deep infiltrating endometriosis was present in 90.1% (182/202) of the included population. Adenomyosis (lesions of the internal and/or the external myometrium) was found in 71.8% (145/202) of the included women. The cumulative LBR was 57.4% (116/202). The women who gave birth were significantly younger (32.0 ± 3.3 versus 33.3 ± 4.1, P = 0.026) and had significantly better ovarian reserve parameters (anti-Müllerian hormone levels, antral follicle count) than those who did not. The presence of adenomyosis, irrespective of the phenotype (76/116 (65.5%) versus 69/86 (80.2%), respectively, P = 0.022) and the presence of T2 high-signal intensity myometrial spots (27/116 (23.3%) and 37/86 (43.0%), respectively, P = 0.003) was significantly less frequent in the group of women who gave birth versus those who did not. After multivariate analysis, the presence of adenomyosis (odds ratio (OR): 0.48, 95% CI (0.29-0.99), P = 0.048) and the presence of T2 high-signal intensity myometrial spots (OR: 0.43, 95% CI (0.22-0.86), P = 0.018) were independently found to be associated with a decrease in the cumulative chance of live birth. LIMITATIONS, REASONS FOR CAUTION: The inclusion of patients from a referral center specialized in the management of women affected by endometriosis could constitute a selection bias, as these women may have had particularly severe forms of adenomyosis and/or endometriosis. A sensitive issue is that there is no consensual classification of adenomyosis and several lesions of adenomyosis can co-exist. Therefore, a comparison of fertility outcomes between women with and without adenomyosis is difficult to perform in practice. WIDER IMPLICATIONS OF THE FINDINGS: In women exhibiting endometriosis, the practitioner should perform an appropriate imaging workup to search for adenomyosis, identify prognostic factors, and personalize the patient management strategy in the setting of ART. STUDY FUNDING/COMPETING INTEREST(S): No funding was obtained and there were no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.