Update on the management of poor ovarian response in IVF: the shiftfrom Bologna criteria to the Poseidon concept

摘要

Despite the considerate progress to which assisted reproduction technology (ART)has been subject since 1978, some issues remain unresolved. Notably, theclinical management of patients with a poor ovarian response is still achallenge in everyday practice, frustrating to both the patient and thefertility expert. Poor ovarian responders (PORs) embody 9–24% of patientsundergoing ovarian stimulation, meaning that up to one in four patients concealsa poor reproductive prognosis. The last decade has witnessed the attempts of themedical community to standardize diagnosis of POR with the developing of theBologna Criteria and the subsequent evolution of the low prognosis patientelaborated in the POSEIDON classification. The aim of this article is tosummarize all evidence concerning etiology and management of poor ovarianresponse, including the most recent advances and future prospects in thisregard. Keywords: Bologna criteria, IVF, poor ovarian responder (POR), poor ovarian response, Poseidon classificationIntroductionThe objective of modern assisted reproduction technology (ART) is the live birth of ahealthy, singleton baby, achieved with reduced time to pregnancy and costs, andincreased patient friendliness and safety. Despite the considerate progress to whichthis branch of medicine has been subject to in the last 40?years, some issues remainunresolved. Notably, the clinical management of patients with a poor ovarianresponse is still a challenge in everyday practice, frustrating to both the patientand the fertility expert.Poor ovarian responders (PORs) embody 9–24% of patients undergoing ovarianstimulation for in vitro fertilization (IVF), meaning that up toone in four patients conceals a poor reproductive prognosis.~(1,2) Etiopathogenesis is complex andonly partly understood; however, some of the recognized etiologies includeage-related depletion of ovarian follicles, advanced endometriosis, chromosomal andgenetic alterations, prior ovarian surgery and pelvic adhesions, metabolic andenzymatic diseases, as well as toxic, autoimmune and infectious diseases.~(3–7) In the last decades, manystudies have investigated many different approaches for the management of PORs;however, they have failed to identify strategies that are unequivocallyeffective.~(8,9)The lack of conclusive evidence is mainly due to the huge discrepancy in thedefinitions of PORs, which makes the comparison of studies and their findingsextremely difficult. Indeed in 2011, a systematic review by Polyzos and Devroey~(9) reported a shocking number of 41 different definitions of POR in 47randomized trials that acted as alarm bells for the medical community. Followingthis publication, the same year, the European Society for Human Reproduction andEmbryology (ESHRE) attempted to reduce the vast heterogeneity underlying thedefinition of POR by introducing the Bologna Criteria (BC).~(10)Bologna criteriaIn the definition of POR by the BC, at least two of the following features must bepresent: advanced maternal age (?40?years), a previous poor ovarian response with ?3oocytes retrieved after conventional stimulation and/or an abnormal ovarian reservetest (ORT) [i.e. antral follicle count (AFC)?