Table 1.

Summary of the existing literature on Poseidon classification.

Author	Publication	Type of article	Main finding
Poseidon Group (Patient-Oriented Strategies Encompassing IndividualizeD Oocyte Number), Alviggi et al. (10)	Fertil Steril. 2016; 105(6):1452–3	Commentary	Definition of Poseidon categories:
			Group 1: Patients < 35 years with sufficient prestimulation ovarian reserve parameters (AFC ≥5, AMH ≥1.2 ng/mL) and with an unexpected poor or suboptimal ovarian response.
			Group 2: Patients ≥ 35 years with sufficient prestimulation ovarian reserve parameters (AFC ≥5, AMH ≥1.2 ng/mL) and with an unexpected poor or suboptimal ovarian response.
			Group 3: Patients < 35 years with poor ovarian reserve prestimulation parameters (AFC < 5, AMH < 1.2 ng/mL).
			Group 4: Patients ≥ 35 years with poor ovarian reserve prestimulation parameters (AFC <5, AMH <1.2 ng/mL).
Humaidan et al. (54)	F1000Res. 2016; 5:2911	Commentary	Definition of Poseidon categories and discussion as to why the new concept has been proposed
Haahr et al. (52)	Reprod Biol Endocrinol. 2018; 16(1):20.	Review	Discussion on how the treatment of the expected poor ovarian response patient should be individualized in all steps of ART, including the choice of GnRH analog, the gonadotropin type and dose, ovulation trigger, and the possible use of adjuvant therapies.
Esteves et al. (53)	Front Endocrinol (Lausanne). 2018; 9:461.	Review	Critical appraisal of the existing criteria that standardize the definition of POR and explanation of reasons for the development of the POSEIDON criteria.