Methods	RCT; 2 parallel groups.
	Unit of randomization: individual.
Participants	Dates of data collection: not reported.
	Setting: Addenbrooke’s Hospital, Cambridge, UK.
	Inclusion criteria: women undergoing emergency CS (in active labor with membrane rupture)
	Exclusion criteria: pyrexia; antibiotic use within 2 weeks.
Interventions	Metronidazole 500 mg (N = 57) vs placebo (N = 58) IV infusion at start of procedure; post-operatively metronidazole or placebo suppository twice daily for 5 days
Outcomes	Pyrexia (> 38°C twice 4 hours apart after first 24 hours); wound infection; endometritis (heavy, offensive lochia and pyrexia); UTI; antibiotic use (15/57 in treatment group vs 20/58 in control group)
Notes	1 woman in the control group developed a pelvic abscess.
	Length of admission not significantly different between the 2 groups (mean 7.4, SD 2. 3 days).
	No adverse reactions occurred.
	Class of antibiotic: Nitroimidazole (metronidazole).
	Subgroups: non-elective CS; before cord clamping.
Risk of bias
Item	Authors’ judgement	Description
Adequate sequence generation?	Unclear	“Randomized, sequential basis.”
		No further information.
Allocation concealment?	Unclear	No information provided.
Blinding?	Yes	Double-blind, placebo controlled.
All outcomes		“Antibiotic … was provided without access to the ‘trial code.”’
Incomplete outcome data addressed?	Yes	No loss to follow up.
All outcomes		No participant excluded.
		ITT analysis.
Free of selective reporting?	Unclear	Insufficient information to judge.
Free of other bias?	Unclear	Comparison of the 2 groups showed similar risk factors.There was insufficient other information which to judge
Overall low risk of bias?	Unclear	Mostly unclear.