Steven R. Lindheim

Wright State University, Boonshoft School of Medicine, Dayton, Ohio

Title: The new American Society for Reproductive Medicine Müllerian Anomalies Classification 2021 interactive website

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Biography

Abstract

Abstract:

The new 2021 Müllerian Anomalies Classification (MAC 2021), formally the 1988 AFS Müllerian Anomaly Classification, is published and ready for prime time. The ultimate goals of MAC 2021 are to simplify communication and recognizability, facilitate accurate and complete literature searches, and better educate across medical disciplines. Most importantly, the underlying impetus for this updated classification is to facilitate and optimize patient care, as some with a müllerian anomaly suffer a significant delay in diagnosis or definitive treatment and many patients wish for better education and advocacy regarding their condition.

Müllerian anomalies are rare reproductive developmental anomalies occurring in 3-6% of females.¹ These anomalies arise due to alterations in the process of müllerian duct formation, fusion and/or canalization that typically occurs during the first 20 weeks of gestation.² However, there is often a significant delay in diagnosis or definitive treatment due to a variability in presentation, imaging, and exam findings.

While there are many proposed classifications, the American Fertility Society (AFS, since renamed as the American Society for Reproductive Medicine (ASRM)) originally published in 1988, it’s müllerian anomaly classification (MAC) system.³ While this classification system has been praised for its simplicity, understandability, and recognizability, it has been criticized for its focus on uterine anomalies, with exclusion of those involving the vagina and cervix; its lack of clear diagnostic criteria; and its inability to classify complex anomalies.  Recognizing these limitations, ASRM created a MAC Task Force that consisted of members of the ASRM, the Society for Reproductive Surgeons, representatives from the North American Society of Pediatric and Adolescent Gynecology, radiologists with expertise in body imaging and diagnosis of müllerian anomalies, and ASRM staff with expertise in education and curriculum design.

The Task Force was tasked with creating a new classification system after reviewing all existing classifications and assessing each for its advantages and disadvantages. It was ultimately determined that an ideal classification should improve identification of Müllerian anomalies, enhance communication between providers and researchers, and ultimately improve clinical care. Given the 1988 AFS Müllerian Anomaly Classification is already universally recognized, it was decided to rebrand and update this classification instead of starting over. The Task Force placed emphasis on keeping the system simple (line drawings); understandable (grouping of anomalies); and recognizable. This updated classification was recently published in Fertility and Sterility and is called the ASRM Müllerian Anomalies Classification 2021 (MAC 2021).⁴

MAC 2021 no longer defines anomalies as numbers (i.e. 1a, IVb) but simply names each category by the described anomaly (i.e. Müllerian agenesis, bicornuate uterus). In addition, three new categories were developed including longitudinal vaginal septum, transverse vaginal septum, and complex anomalies. Furthermore, MAC 2021 has been expanded from a static reference into an educational tool and made into an accessible interactive format that details each of the nine anomaly classifications (https://connect.asrm.org/education/asrm-mac-2021/asrm-mac-2021?ssopc=1).⁵ This interactive website details for each anomaly category the known variants including their description, depiction, and alternatively used names; anomalies with a similar presentation or appearance; expected presentation; imaging including magnetic resonance imaging, hysterosalpingogram, and ultrasound findings with pictures; and medical and surgical treatment options. As the preferred Müllerian anomaly classification,  MAC 2021 simplifies communication and recognizability, facilitates literature searches, better educates across medical disciplines, and most importantly as a result, is ideal for patient care. Best yet, the interactive feature will allow the ASRM MAC 2021 classification to be updated to reflect new anomalies and information moving forward without having to wait another 33 years to update and/or rebrand. We encourage all providers who see and treat those with müllerian anomalies to go online, interact with this tool, and “read all about it”⁴ to better communicate and optimize clinical outcomes!