Table 2.

Extracted data regarding the stimulation protocols employed for FPS and LPS respectively

Studies	Stimulation protocols employed
	FPS	First trigger	Pre-existing follicles required for LPS	Initiation of LPS (days following 1st OR)	LPS	Second trigger
Kuang et al. 2014 [6]	CC, Let, HMG	GnRH-ag, Ibup	At least 2 antral follicles 2–8 mm	0–1 days	Let, HMG, Medrox	GnRH-ag, Ibup
Ubaldi et al. 2016 [9]	rFSH, rLH, GnRH-antag	Bus	NA	5 days	rFSH, rLH, GnRH-antag	Bus
Liu et al. 2017 [20]	rFSH, rLH	rHCG	At least one antral follicle 6–11 mm	1–3 days	HMG	rHCG
Zhang et al. 2017 [21]	CC, Gon	GnRH-ag	Antral follicles 5–10 mm	1 day	Gon	rHCG
Rashtian et al. 2017 [7]	Let, CC, Gon, GnRH-antag	GnRH-ag	At least 1 antral follicle < 11 mm	1 day	Let, CC, Gon	rHCG
Jin et al. 2018 [19]	Let or CC, HMG, GnRH-antag	GnRH-ag	NA	1–3 days	CC, HMG	rHCG
Vaiarelli et al. 2018 [10]	E2 valerate, rFSH, rLH, GnRH-antag	Bus	NA	5 days	rFSH, rLH, GnRH-antag	Bus
Zhang et al. 2018 [22]	CC, HMG	rHCG	At least 2 antral follicles 2–8 mm	2–7 days	CC, HMG	rHCG
Madani et al. 2019 [16]	CC, Let, HMG	Bus, Ibup	At least 2 antral follicles 2–8 mm	1 day	Let, HMG	Bus

FPS follicular phase stimulation, LPS luteal phase stimulation, OR oocyte retrieval, CC clomiphene citrate, HMG human menopausal gonadotropin, rFSH recombinant FSH, rLH recombinant LH, rHCG recombinant human chorionic gonadotropin, Gon exogenous gonadotropins, GnRH-ag GnRH agonist, GnRH-antag GnRH antagonist, Bus buserelin, Ibup ibuprofen, Let letrozole, Medrox medroxyprogesterone acetate, NA not applicable