Shi 2016.

Study characteristics
Methods	Prospective randomised study in China IVF and ICSI Time period of study not known Fresh ET on Day 3
Participants	178 patients aged 35 to < 42 years
Interventions	LAH on Day 3 embryos Laser thinning of zona Experimental group had LAH (n = 82) (53 IVF and 29 ICSI) Control group had no LAH (n = 96) (70 IVF and 26 ICSI)
Outcomes	Live birth, clinical pregnancy, miscarriage, multiple pregnancy rates
Notes	No loss to follow‐up in both groups Study registered on clinical trial registry at clinicaltrial.gov: NCT01765322
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	States only that patients were randomly allocated to AH group and control group but provides no details
Allocation concealment (selection bias)	Unclear risk	No information
Blinding (performance bias and detection bias) All outcomes	High risk	Open‐label study
Incomplete outcome data (attrition bias) All outcomes	Low risk	No losses to follow‐up; outcomes reported for all
Selective reporting (reporting bias)	Unclear risk	No information about monozygotic twins provided even though multiple pregnancy rates provided. Results for IVF/ICSI not provided separately
Other bias	Low risk	None identified Study reported primary and secondary outcomes as stated on clinical trials registry