Source and identification	Study ID
	Review author
	Citations and related records
	Contact details of study author
	Correspondence required	No	Yes	Questions
	Sponsorship source
	Country
	Year study published
	Data lacking?
	Study author's key conclusions
	Other comments of reviewer
Methods	Study design and group
	Study duration
	Sample size
	Setting
"Risk of bias" table	Domain	Description			Judgement
	Adequate sequence generation?				High	Low	Unclear
	Adequate allocation concealment?				High	Low	Unclear
	Blinding of participants and personnel?				High	Low	Unclear
	Blinding of outcome assessors (per outcome)?				High	Low	Unclear
	Incomplete outcome data assessed?				High	Low	Unclear
	Free of selective reporting?				High	Low	Unclear
	Other concerns re bias?				High	Low	Unclear
	Risk of bias				High	Low	Unclear
Participants	Total number of participants randomised
	Baseline characteristics (per group) ‐ Age ‐ Sex ‐ Nationality ‐ Number per group ‐ Lifestyle characteristics (BMI...) ‐ Fertility characteristics (type of infertility and treatment, phase of treatment)	Control		Intervention
	Baseline differences
	Inclusion criteria
	Exclusion criteria
	Other comments ‐ participants
Interventions	Number of intervention groups
	Details of interventions (per group) ‐ Category ‐ Description ‐ Duration ‐ Frequency ‐ Setting ‐ Mode of delivery ‐ Integrity/compliance ‐ Other comments on interventions	Control		Intervention
Outcomes	Outcome name
	Outcome type (continuous/dichotomous)
	Outcome reported as... (choose from RR, OR, mean, and SD, or custom‐made in Covidence)
	Definition and unit of measurement Scale, range, and direction (if relevant)
	Data value (change from baseline/endpoint)
	Time point of outcome assessed
	Other comments on outcomes
Results	Summary data (in Covidence)
		Event: e.g. live birth	No event: e.g. live birth	Total (by group)
	Intervention: preconception lifestyle advice
	Control: no preconception lifestyle advice
	Total (by event)
	Estimate of effect with confidence interval; P value