Can a consensus and evidence-driven set of terms and definitions be generated to be used globally in order to ensure consistency when reporting on infertility issues and fertility care interventions, as well as to harmonize communication among the medical and scientific communities, policy-makers, and lay public including individuals and couples experiencing fertility problems?
Summary Answer
A set of 283 consensus-based and evidence-driven terminologies used in infertility and fertility care has been generated through an inclusive consensus-based process with multiple stakeholders.
What Is Known Already
In 2006 the International Committee for Monitoring Assisted Reproductive Technologies (ICMART) published a first glossary of 53 terms and definitions. In 2009 ICMART together with WHO published a revised version expanded to 87 terms, which defined infertility as a disease of the reproductive system, and increased standardization of fertility treatment terminology. Since 2009, limitations were identified in several areas and enhancements were suggested for the glossary, especially concerning male factor, demography, epidemiology and public health issues.
Study Design, Size, Duration
Twenty-five professionals, from all parts of the world and representing their expertise in a variety of sub-specialties, were organized into five working groups: clinical definitions; outcome measurements; embryology laboratory; clinical and laboratory andrology; and epidemiology and public health. Assessment for revisions, as well as expansion on topics not covered by the previous glossary, were undertaken. A larger group of independent experts and representatives from collaborating organizations further discussed and assisted in refining all terms and definitions.
Participants/Materials, Setting, Methods
Members of the working groups and glossary co-ordinators interacted through electronic mail and face-to-face in international/regional conferences. Two formal meetings were held in Geneva, Switzerland, with a final consensus meeting including independent experts as well as observers and representatives of international/regional scientific and patient organizations.
MAIN RESULTS AND THE ROLE OF CHANCE: A consensus-based and evidence-driven set of 283 terminologies used in infertility and fertility care was generated to harmonize communication among health professionals and scientists as well as the lay public, patients and policy makers. Definitions such as 'fertility care' and 'fertility awareness' together with terminologies used in embryology and andrology have been introduced in the glossary for the first time. Furthermore, the definition of 'infertility' has been expanded in order to cover a wider spectrum of conditions affecting the capacity of individuals and couples to reproduce. The definition of infertility remains as a disease characterized by the failure to establish a clinical pregnancy; however, it also acknowledges that the failure to become pregnant does not always result from a disease, and therefore introduces the concept of an impairment of function which can lead to a disability. Additionally, subfertility is now redundant, being replaced by the term infertility so as to standardize the definition and avoid confusion.
Limitations, Reasons for Caution
All stakeholders agreed to the vast majority of terminologies included in this glossary. In cases where disagreements were not resolved, the final decision was reached after a vote, defined before the meeting as consensus if passed with 75%. Over the following months, an external expert group, which included representatives from non-governmental organizations, reviewed and provided final feedback on the glossary.
Wider Implications of the Findings
Some terminologies have different definitions, depending on the area of medicine, for example demographic or clinical as well as geographic differences. These differences were taken into account and this glossary represents a multinational effort to harmonize terminologies that should be used worldwide.
Zegers-Hochschild Adamson Dyer international glossary infertility fertility care 2017, ICMART WHO ESHRE ASRM FIGO consensus terminology reproductive medicine definitions, infertility definition 12 months unprotected intercourse inability conceive, ART IVF ICSI terminology standardized definitions international consensus glossary, Human Reproduction 2017 international glossary 283 terms fertility care definitions, subfertility fecundity infertility clinical pregnancy live birth standard definitions, ovarian reserve diminished response poor responder standardized terminology, surrogacy donor gametes fertility preservation cryopreservation defined terms, reproductive medicine terminology harmonization global communication consensus, assisted reproduction outcome reporting standardized definitions glossary revision
PMID 29117321 29117321 DOI 10.1093/humrep/dex234 10.1093/humrep/dex234 Zegers-Hochschild et al. 2017, Zegers-Hochschild 2017
Cite this article
Zegers-Hochschild, F., Adamson, G. D., Dyer, S., Racowsky, C., de Mouzon, J., Sokol, R., Rienzi, L., Sunde, A., Schmidt, L., Cooke, I. D., Simpson, J. L., & van der Poel, S. (2017). The International Glossary on Infertility and Fertility Care, 2017. Human reproduction (Oxford, England), 32(9), 1786-1801. https://doi.org/10.1093/humrep/dex234
Zegers-Hochschild F, Adamson GD, Dyer S, Racowsky C, de Mouzon J, Sokol R, et al. The International Glossary on Infertility and Fertility Care, 2017. Hum Reprod. 2017;32(9):1786-1801. doi:10.1093/humrep/dex234
Zegers-Hochschild, F., et al. "The International Glossary on Infertility and Fertility Care, 2017." Human reproduction (Oxford, England), vol. 32, no. 9, 2017, pp. 1786-1801.
Related articles
Diagnostic Criteria and Classification · Terminology and Definitions
Minjeur M et al., 2026·Journal of Restorative Reproductive Medicine
Infertility is a clinical condition that is recognized by the symptom of an inability to conceive through sexual intercourse or to sustain a pregnancy, with that symptom indicating underlying male and/or female pathology.
This definition of infertility was developed through a structured, consensus-informed process involving broad stakeholder engagement. Initially, multiple definitions currently used by various medical professional organizations were reviewed, and a definition document was drafted and submitted to the Board of Directors of the International Institute for Restorative Reproductive Medicine (IIRRM). All IIRRM members were invited to provide feedback on the draft. Approximately 2,500 individuals and 44 organizations from 92 countries were then invited to review the proposed document, representing clinical, scientific, patient, policy, and advocacy perspectives. Submitted comments were reviewed thematically, with suggested revisions evaluated for clarity, clinical relevance, inclusiveness, and consistency with contemporary restorative reproductive medicine. Following this review, 3 substantive changes, 18 minor changes, and 15 citation corrections were incorporated into the final draft which resulted in a revised definition intended to better reflect the medical, social, and practical realities of modern infertility evaluation and care. Final approval by the IIRRM Board of Directors was unanimous.
Diagnostic Criteria and Classification · Terminology and Definitions
Teede HJ et al., 2026·Lancet (London, England)·
Open Access
Polyendocrine metabolic ovarian syndrome (PMOS), previously named polycystic ovary syndrome (PCOS), affects one in eight women. However, the term PCOS is inaccurate, implying pathological ovarian cysts, obscuring diverse endocrine and metabolic features, and contributing to delayed diagnosis, fragmented care, and stigma, while curtailing research and policy framing. Building on an international mandate for change, we outline an unprecedented, rigorous, multistep global consensus process for the name change. Funding and governance were established with engagement of 56 leading academic, clinical, and patient organisations. Using iterative global surveys (with responses from 14 360 people with PCOS and multidisciplinary health professionals from all world regions), modified Delphi methods, nominal group technique workshops, and marketing and implementation analyses, we identified principles prioritising scientific accuracy, clarity, stigma avoidance, cultural appropriateness, and implementation feasibility. An accurate new name was prioritised over retaining the PCOS acronym or a generic name. Implementation approaches prioritised evolution rather than transformation. Preferred terms were polyendocrine, metabolic, and ovarian, reflecting the condition's multisystem pathophysiology, and polyendocrine metabolic ovarian syndrome was the consensus new name. Accuracy was improved by omitting cysts and by capturing endocrine, metabolic, and ovarian dysfunction. A co-designed global implementation strategy, including a transition period, education, and alignment with health systems and disease classification, is under way.
Traditionally, IVF success rates have been reported in terms of live birth per fresh cycle or embryo transfer. With the increasing use of embryo freezing and thawing it is essential that we report not only outcomes following fresh but also those after frozen embryo transfer as a complete measure of success of an IVF treatment. Most people agree that an individual's chance of having a baby following fresh and frozen embryo transfer should be described as cumulative live birth rate. However, views on the most appropriate parameters required to calculate such an outcome have been inconsistent. There is an additional dimension - time for all frozen embryos to be used up by a couple, which can influence the outcome. Given that cumulative live birth rate is generally perceived to be the preferred reporting system in IVF, it is time to have an international consensus on how this statistic is calculated, reported and interpreted by stakeholders across the world.
Diagnostic Criteria and Classification · Terminology and Definitions
Lisa M Lix et al., 2012·BMC Public Health·
Open Access
Population-based administrative data have been used to study osteoporosis-related fracture risk factors and outcomes, but there has been limited research about the validity of these data for ascertaining fracture cases. The objectives of this study were to: (a) compare fracture incidence estimates from administrative data with estimates from population-based clinically-validated data, and (b) test for differences in incidence estimates from multiple administrative data case definitions. Thirty-five case definitions for incident fractures of the hip, wrist, humerus, and clinical vertebrae were constructed using diagnosis codes in hospital data and diagnosis and service codes in physician billing data from Manitoba, Canada. Clinically-validated fractures were identified from the Canadian Multicentre Osteoporosis Study (CaMos). Generalized linear models were used to test for differences in incidence estimates. For hip fracture, sex-specific differences were observed in the magnitude of underand over-ascertainment of administrative data case definitions when compared with CaMos data. The length of the fracture-free period to ascertain incident cases had a variable effect on over-ascertainment across fracture sites, as did the use of imaging, fixation, or repair service codes. Case definitions based on hospital data resulted in under-ascertainment of incident clinical vertebral fractures. There were no significant differences in trend estimates for wrist, humerus, and clinical vertebral case definitions. The validity of administrative data for estimating fracture incidence depends on the site and features of the case definition.