The classification system has been created to replace the much-modified World Health Organization system first described in 1973. Since that time, many modifications have been proposed to accommodate advances in imaging and new information about underlying pathologies.
The newHyPO-P system is based largely on anatomy. The acronym refers to ovulatory disorders related to the hypothalamus (type I), the pituitary (type II), and the ovary (type III).
Polycystic ovary syndrome (PCOS), one of the most common ovulatory disorders, was given a separate category (type IV) as it is complex and is a heterogeneous systemic disorder with manifestations not limited to an impact on ovarian function.
The new system is not as focused on the specific steps for investigation of ovulatory dysfunction as much as it explains how to structure an investigation of the girl or woman with an ovulatory disorder and then how to characterise the underlying cause. It is designed to allow everyone, whether clinicians, researchers, or patients, to speak the same language
The structure of this system is expected to lead to greater precision in understanding the causes and defining features of ovulatory disorders.
The most important contribution of this new classification system are standardisation and communication. The system will be amenable for educating trainees and patients, for communicating between clinicians, and as a framework for research.
