Rimington 1997.

Methods	Randomised prospective study conducted in a Fertility clinic in Wales, UK Timing: not stated
Participants	50 women, mean age in IVF group was 31 (95% CI 29.8 to 32.2) and for LOE + IVF the mean age was 31.8 (95% CI 30.3 to 33.2) Inclusion: Diagnosis of PCOS, requiring IVF for reasons other than anovulation, at least 1 previous unsuccessful ovarian stimulation cycle with gonadotrophins Exclusion: Aged > 40 years, history of > 2 miscarriages, severe male‐factor infertility
Interventions	IVF (n = 25), versus Ovarian electrocautery and IVF (grid of holes 10 mm apart) ovarian stimulation started 1 week after LOE (n = 25). Follow‐up for 1 cycle
Outcomes	Number of abandoned cycles, OHSS, pregnancy, miscarriage
Notes	Conflict of interest: not stated
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Blocked method of randomisation.."
Allocation concealment (selection bias)	Unclear risk	No details in paper
Blinding of participants and personnel (performance bias) All outcomes	High risk	There was no evidence of blinding of researchers or participants
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No details provided
Incomplete outcome data (attrition bias) All outcomes	Low risk	All women randomised appear to be analysed
Selective reporting (reporting bias)	Unclear risk	We could not retrieve the original protocol. All outcomes listed in the Methods section were reported in the Results
Other bias	Low risk	No evidence of other risk of bias