Table 1. Characteristics of the studies included the meta analysis of long agonist versus antagonist protocols in polycystic ovary syndrome.

Author and Year	study size(n1/n2)	RCT	Inclusion criteria	Long agonist protocol		Antagonist protocol
				OC pretreatment	Protocol	OC pretreatment	Protocol
Hwang et al., 2004	24/25	yes	at least one of the two hormonal abnormalities. The exclusion criteria: included patients older than 38 years or with serum FSH levels>.12 mIU/ml.	no	Buserelin acetate 500 mg/day was administrated from day 3 of induced or spontaneous menstruation. for 14 days, dosage was decreased to 250 mg/day at the beginning of HMG administration. until the day of HCG injection.	yes	Cetrorelix acetate was then initiated with a single dose of 0.25 mg administered on day 3, From day 4 to day 9 reduced to 0.125 mg/day, increased to 0.25 mg/day from day 10 until the day before HCG
Mahnaz Ashrafi, 2005	24/23	yes	thyroid tests and prolactin were normal. PCOS patients under 35 years old	yes	standard long GnRH analogue protocol	yes	Then GnRH antagonist (0.25 mg) was administered from 6th day after HMG initiation (LH≤5 IU/ml) to the day of HCG injection
Trifon G.Lainas 2007	52/26	yes	age 18–39 years, less than three previous IVF/ICSI attempts, no endometriotic cyst present as assessed by transvaginal ultrasound examination and basal hormonal levels of FSH in the early follicular phase of<10 IU/L. previous poor ovarian response were excluded.	yes	administered s.c. GnRH agonist 0.1 mg triptorelin daily started 3 days before discontinuation of the oral contraceptive.	yes	A daily s.c. dose of 0.25 mg ganirelix on Day 2 of menses (Day 1 of stimulation) that followed the discontinuation of the OCP.
Rafal Kurzawa 2008	37/33	yes	age≤35 years; body mass index<26 kg/m2; FSH<12 mIU/ml on the third day of the cycle. Exclude: ≥2 miscarriages, ≥3 unsuccessful IVF/ICSI cycles, anatomical abnormalities of the uterus on laparoscopy or hysteroscopy and existence of ovarian cysts.	yes	on days 16–18 of the preceding cycle, after transvaginal ultrasonographic screening of ovaries, an intramuscular injection of GnRH agonist triptorelin	yes	cetrorelix 0.25 mg was administered daily subcutaneous injections when at least two ovarian follicles reached 14 mm in diameter
Marzieh Agha Hosseini. 2010	55/57	yes	less than 35 years of age with a normal BMI of <27 kg/m2), normal prolactin and thyroid hormone levels	yes	GnRH agonist buserelin 500 mg subcutaneously was started on day 21 of the previous cycle.	yes	When a follicllar diameter of 14 mm was obtained, cetrorelix 0.25 mg/day was injected subcutaneously for 3 subsequent days.
Trifon G. Lainas, 2010	110/110	yes	age 18–39 years, no endometriotic cyst present, basal hormonal levels of FSH in the early follicular phase of <10 IU/ml. Patients with known previous poor ovarian response were excluded.	yes	GnRH agonist 0.1 mg triptorelin daily, decreased on that day to 0.05 mg/day and continued until and including the day of triggering	yes	flexible GnRH antagonist protocol daily s.c administration of ganirelix 0.25 mg initiated when at least one of the following criteria were fulfilled: (i) the presence of at least one follicle measuring .14 mm; (ii) serum E2 levels .600 pg/ml; and (iii) serum LH levels >10 IU/l.
Ensieh Shahrokh, 2010	45/45	yes	<35 years basal FSH<10 IU/L and undergoing their first cycle of the ART. excluded :secondary infertility, previous IVF or ICSI, thyroid dysfunction, hyper-prolactinemia, uterine abnormality and solitary ovary.	yes	500 mcgr Buserelin per day commenced on day 19–20 of OCP cycle.	yes	Administration of 0.25 mg Cetrolix acetate SQ daily initiated as soon as the follicles reached a size of 12–14 mm and continued every morning after wards, including the day of trigger.
Chung-Hoon Kim, 2012	105/106	yes	aged 25 to 39 years were randomized	yes	GnRH agonist, triptorelin at a dose of 0.1 mg/day was initiated from day 18 of OC pretreatment cycle. ovarian stimulation was started and the dose of triptorelin was reduced to 0.05 mg daily and continues up to day of rhCG administration.	yes	GnRH antagonist, 0.125 mg/day was administered in the morning of stimulation day 1 and 2. When the mean diameter of lead follicle reached 13 mm, cetrorelix at a dose of 0.25 mg/day was started again and continued daily up to the day of recombinant hCG
Bulent, 2012	150/150	yes	PCOS (age 23∼35 y) were recruited. All selected couples were in their first IVF/ICSI cycles. Women with PCOS, BMI 20∼30 kg/m2 were included .excluded women with PCOS whose ovaries did not appear polycystic.	yes	ovarian downregulation was initiated with daily leuprolide acetate 1 mg beginning on day 21 of the preceding menstruation. After ovarian suppression was achieved, the dose was reduced to 0.5 mg until the day of hCG.	yes	the fixed GnRH antagonist protocol daily s.c administration of ganirelix 0.25 mg was initiated on day 6 of gonadotropin until hCG administration stimulation.