Balakier 2009.

Methods	Single centre Unclear if power calculation performed ITT analysis unclear Published as full paper
Participants	84 women from Canada with no more than one unsuccessful previous IVF attempt, aged ≤ 37 years of age, and with a day 3 FSH ≤ 10mIU/mL Mean age: Control: 33.8 ± 3.2; AH: 32.5 ± 3.8 54 women underwent their first IVF cycle, the other 30 (13 AH) their second cycle.
Interventions	Laser assisted thinning n = 45: the total length of laser cut was approximately 30‐40μm, and about 60‐80% of the outer layer of the zona pellucid was thinned without complete breaching, applying 2ms laser beams. versus control n = 39
Outcomes	Clinical pregnancy;Multiple pregnancies; Spontaneous miscarriages; Live births
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Computer‐generated randomisation list
Allocation concealment (selection bias)	Unclear risk	No details in text
Blinding (performance bias and detection bias) All outcomes	Low risk	The study was double blinded to patients and medical personnel
Incomplete outcome data (attrition bias) All outcomes	Low risk	There were no losses to follow up and all women were analysed
Selective reporting (reporting bias)	Unclear risk	Original protocol not viewed. Live birth was reported