Methods	Randomized placebo controlled trial; 3 parallel groups.
	Unit of randomization: individual.
Participants	Dats of data collection: not reported.
	Setting: Jersey City Medical Center, New Jersey; predominantly lower socio-economic indigent women Inclusion criteria: women
	undergoing primary CS after onset of labor (corresponds to the definition of non-elective)
	Exclusion: febrile or infected, allergy to pipericillin.
Interventions	Pipericillin 4 g peri-operatively (N = 50) vs pipericillin 4 g peri-operatively and at 4 and 8 hours post-operatively (N = 50) vs placebo (N = 50); both treatment groups combined in analysis
Outcomes	Febrile morbidity (> 38.0°C twice at least 6 hours apart after first post-operative day) ; endometritis (fever, tender uterus and purulent lochia); hospital stay (no significant difference, variance not given)
Notes	Use of saline or antibiotic lavage not allowed.
	No adverse reactions reported with treatment.
	Class of antibiotic: ureidopenicillin (pipericillin).
	Subgroups: non-elective CS; after cord clamping.
Risk of bias
Item	Authors’ judgement	Description
Adequate sequence generation?	Unclear	“…randomly divided…”
Allocation concealment?	Unclear	No information provided.
Blinding?	Unclear	Described as blinded.
All outcomes
Incomplete outcome data addressed?	Unclear	No losses or exclusions were reported. The analysis appears to be by ITT
All outcomes
Free of selective reporting?	Unclear	Insufficient information to judge.
Free of other bias?	Unclear	The 3 groups were comparable regarding number of vaginal exams, haemoglobin levels and other risk factors. However, there was insufficient information to judge overall
Overall low risk of bias?	Unclear	Unclear.