Abu Hashim 2011a.

Methods	Randomised prospective trial conducted in Egypt
Participants	282 women attending fertility clinics in Egypt. Mean age of women in the metformin group was 27.2 ± 2.5 years and in the LOD group was 26.5 ± 2.3 years Inclusion: Clomiphene‐resistant PCOS, patent fallopian tubes assessed by hysterosalpingography, normal semen analysis from partner, normal serum prolactin, thyroid stimulating hormone and 17‐hydroyprogesterone Exclusion: Other causes of infertility, age > 40 years, contraindications to anaesthesia and having received metformin, gonadotrophin or OCP in preceding 6 months
Interventions	Metformin 500 mg 3 times a day for 6 to 8 weeks, followed by 100 mg of clomiphene citrate for 5 days starting on day 3 of spontaneous or induced menstruation. Dosage increased by 50 mg at next cycle if still anovulatory; treated for 6 cycles (n = 138), versus LOD: each ovary was cauterised at 4 points and women were followed up for 6 months (n = 144).
Outcomes	Pregnancy, miscarriage, ovulation rate, endometrial thickness
Notes	Author contacted in September 2011 for details on pregnancy rates by woman rather than by cycle