Comparison of the ESHRE–ESGE and ASRM classifications of Müllerian duct anomalies in everyday practice

STUDY QUESTION Does the European Society of Human Reproduction and Embryology–European Society for Gynaecological Endoscopy (ESHRE–ESGE) classification of female genital tract malformations significantly increase the frequency of septate uterus diagnosis relative to the American Society for Reproductive Medicine (ASRM) classification? SUMMARY ANSWER Use of the ESHRE–ESGE classification, compared with the ASRM classification, significantly increased the frequency of septate uterus recognition. WHAT IS KNOWN ALREADY The ESHRE–ESGE criteria were supposed to eliminate the subjective diagnoses of septate uterus by the ASRM criteria and replace the complementary absolute morphometric criteria. However, the clinical value of the ESHRE–ESGE classification in daily practice is difficult to appreciate. The application of the ESHRE–ESGE criteria has resulted in a significantly increased recognition of residual septum after hysteroscopic metroplasty, with a possible risk of overdiagnosis of septate uterus and problems for its management. STUDY DESIGN, SIZE, AND DURATION A prospective observational study was performed with 261 women consecutively enrolled between June and September 2013. PARTICIPANTS/MATERIALS, SETTING, AND METHODS Non-pregnant women of reproductive age presented for evaluation to a private medical center. A gynecological examination and 3D ultrasonography were performed to assess the anatomy of the uterus, cervix and vagina. Congenital anomalies were diagnosed using the ASRM classification with additional morphometric criteria as well as with the ESHRE–ESGE classification. We compared the frequency and concordance of diagnoses of septate uterus and all congenital malformations of the uterus according to both classifications. The morphological characteristics of septate uterus recognized by both criteria were compared. MAIN RESULTS AND ROLE OF CHANCE Of the 261 patients enrolled in this study, septate uterus was diagnosed in 44 (16.9%) and 16 (6.1%) patients using the ESGE–ESHRE and ASRM criteria, respectively [relative risk (RR)ESHRE–ESGE:ASRM 2.74; 95% confidence interval (CI), 1.6–4.72; P < 0.01]. At least one congenital anomaly were diagnosed in 58 (22.2%) and 43 (16.5%) patients using the ESHRE–ESGE and ASRM classifications (RRESHRE–ESGE:ASRM, 1.35; 95% CI, 0.95–1.92, P = 0.1), respectively. The two criteria had moderate strength of agreement in the diagnosis of septate uterus (κ = 0.45, P < 0.01). There was good agreement in differentiation between anomaly and norm between the two assessment criteria (κ = 0.79, P < 0.01). The percentages of all congenital malformations and results of the differentiation between the anomaly and norm were obtained after excluding the confounding original ESHRE–ESGE criterion of dysmorphic uterus (internal indentation <50% uterine wall thickness). The morphology of septa identified by the ESHRE–ESGE [length of internal fundal indentation (mm): median 10.7; lower–upper quartile, 8.1–20] significantly differed (P < 0.01) from that identified by the ASRM criteria [length of internal fundal indentation (mm): median, 21.1; lower–upper quartile, 18.8–33.1]. Internal fundal indentation in 16 out of 44 (36.4%) cases was <1 cm in the septate uterus by ESHRE–ESGE and met the criteria for normal uterus by ASRM. LIMITATIONS AND REASONS FOR CAUTION The study participants were women who visited a diagnostic and treatment center specialized in uterine congenital malformations for a medical assessment, not from the general public. WIDER IMPLICATIONS OF THE FINDINGS Septate uterus diagnosis by ESHRE–ESGE was quantitatively dominated by morphological states corresponding to arcuate uterus or cases that were not diagnosed as congenital malformations by ASRM. Relative overdiagnosis of septate uterus by ESHRE–ESGE in these cases may lead to unnecessary overtreatment without the expected benefits. The ESHRE–ESGE classification criteria should be redefined due to confusions in the methodology. Until the criteria are revised, septate uterus should not be diagnosed using this classification system and it should not be used as an eligibility criterion for hysteroscopic metroplasty. STUDY FUNDING/COMPETING INTEREST(S) This work was supported by Jagiellonian University (grant no. K/ZDS/003821). The authors have no competing interests to declare.