The FIGO Ovulatory Disorders Classification System
Malcolm G. Munro, Adam Balen, SiHyun Cho, Hilary Critchley, Ivonne Díaz, Rui Alberto Ferriani, Laurie Henry, Edgar Mocanu, Zephne M. van der Spuy, Ganesh Acharya, Georgios Adonakis, Sadiah Ahsan, Taghreed AIhaidari, Tengiz Asatiani, Ricardo Azziz, Adam Balen, Michela Bedard, Jennifer Blake, Veronica Chamy, Ying Cheong, Vincent Y.T. Cheung, SiHyun Cho, Hilary Critchley, Jose Teixeira da Silva, Ivonne Díaz, Colin Duncan, Amelie Ekersley, Roberto Epifanio-Malpassii, Abimbola O. Famuyide, Rui Alberto Ferriani, Linda C. Giudice, Maargarita Gurevich, Sioḃán D. Harlow, Roger Hart, Oskari Heikinheimo, Laurie Henry, Sulaiman Heylen, Richard H. Kennedy, Anna Klepchuckova, Petr Křepelka, Paul le Roux, Kateryna Levchenko, Dimitrios Loutradis, Erica E. Marsh, Noni Martins, Raj Mathur, Thabo Matsaseng, Rui Filipe Oliveira Miguelote, Edgar Mocanu, Malcolm G. Munro, Eugène Ngoga, Michelle Nisolle, Robert J. Norman, Masanori Ono, Axelle Pintiaux, Gunda Pristauz-Telsnigg, Diana Ramašauskaitė, Pernille Ravn, José Eduardo Reis, P. Roos, Irena Rozic, Anibal Scarella, Katsiaryna Sharai, Alena Shibut, Sony Sierra, Anne Z. Steiner, Stoop Dominic, Bettina Tóth, Zephne M. van der Spuy, Saskia Williams, Lauren A. Wise, Anusch Yazdani, Liudmila Zhaunova, Meggan Zunckel, Karabo Zwane
Abstract
Ovulatory disorders are common causes of amenorrhea, abnormal uterine bleeding and infertility and are frequent manifestations of polycystic ovary syndrome (PCOS). There are many potential causes and contributors to ovulatory dysfunction that challenge clinicians, trainees, educators, and those who perform basic, translational, clinical and epidemiological research. Similarly, therapeutic approaches to ovulatory dysfunction potentially involve a spectrum of lifestyle, psychological, medical and procedural interventions. Collaborative research, effective education and consistent clinical care remain challenged by the absence of a consensus comprehensive system for classification of these disorders. The existing and complex system, attributed to the World Health Organization (WHO), was developed more than three decades ago and did not consider more than 30 years of research into these disorders in addition to technical advances in imaging and endocrinology. This article describes the development of a new classification of ovulatory disorders performed under the aegis of the International Federation of Gynecology and Obstetrics (FIGO) and conducted using a rigorously applied Delphi process. The stakeholder organizations and individuals who participated in this process comprised specialty journals, experts at large, national, specialty obstetrical and gynecological societies, and informed lay representatives. After two face-to-face meetings and five Delphi rounds, the result is a three-level multi-tiered system. The system is applied after a preliminary assessment identifies the presence of an ovulatory disorder. The primary level of the system is based on an anatomic model (Hypothalamus, Pituitary, Ovary) that is completed with a separate category for PCOS. This core component of the system is easily remembered using the acronym HyPO-P. Each anatomic category is stratified in the second layer of the system to provide granularity for investigators, clinicians and trainees using the 'GAIN-FIT-PIE' mnemonic (Genetic, Autoimmune, Iatrogenic, Neoplasm; Functional, Infectious and Inflammatory, Trauma and Vascular; Physiological, Idiopathic, Endocrine). The tertiary level allows for specific diagnostic entities. It is anticipated that, if widely adopted, this system will facilitate education, clinical care and the design and interpretation of research in a fashion that better informs progress in this field. Integral to the deployment of this system is a periodic process of reevaluation and appropriate revision, reflecting an improved understanding of this collection of disorders.