Shaker 1995.

Methods	Parallel group study. Number of women randomized: 49 (number per group not reported; 22 cycles in intervention group; 29 cycles in control group) but total number of cycles not the same as total number of women randomized. Number of withdrawals: 11 cycles (3 in intervention group: 2 due to poor response, 1 due to failure of embryo cleavage; 8 in control group: 3 due to conversion to IUI, 1 due to poor response, 2 due to failed fertilisation, 2 due to risk of OHSS). Number of women analyzed: unclear. Duration of study: 8 months of recruitment.
Participants	Country of authors: UK. Inclusion criteria: women who underwent IVF treatment cycles and had an ovarian cyst > 15 mm in diameter or an endometrial thickness > 5 mm and serum oestradiol concentration > 100 pmol/L after 14 days of GnRH agonist (buserelin acetate) treatment Exclusion criteria: relevant uterine or ovarian pathology. Mean age ± SEM: intervention group: 36.0 ± 0.86 years; control group: 35.72 ± 0.69 years.
Interventions	Intervention: GnRH agonist (buserelin acetate 500 μg/day) started cycle day 2 or 3 + progestogen (100 mg IM single dose) on cycle day 16 or 17 + hMG, started when serum oestradiol concentration ≤ 100 pmol/L. Control: GnRH agonist (buserelin acetate 500 μg/day), started cycle day 2 or 3 + hMG, started when serum oestradiol concentration ≤ 100 pmol/L. hMG start dose according to women's age, baseline serum FSH level, response to stimulation in previous treatment cycles. hMG and GnRH agonist both continued until hCG injection (10,000 IU), administered when 3 follicles ≥ 18 mm in diameter.
Outcomes	Clinical pregnancy rate: not defined. Serum oestradiol levels on day of recruitment. Number of days of hMG administration. Number of days of GnRH agonist. Endometrial thickness. Mean diameter of ovarian cyst on day of recruitment and 6 days later. Total number of hMG ampoules. Number of follicles. Number of oocytes retrieved. Number of embryos transferred.
Notes	Power calculation performed: no. ITT analysis performed: unclear.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Randomization was done by drawing sequentially labelled sealed envelops, each containing a number obtained from a table of random numbers."
Allocation concealment (selection bias)	Low risk	Sealed envelopes.
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Not reported.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Reasons for withdrawals and proportions of participants who withdrew not reported per treatment group.
Selective reporting (reporting bias)	Low risk	Data on all planned outcomes reported.
Other bias	Low risk	No significant differences in baseline characteristics between groups with regard to age, length of infertility, number of previous IVF cycles and cause of infertility.