Methods	RCT; 2 parallel groups.
	Unit of randomization: individual.
Participants	Dates of data collection; not reported.
	Setting: University of Michigan Medical Center, Ann Arbour, Michigan, US
	Inclusion criteria: women in labor.
	Exclusion criteria: acute bleeding due to abruptio placentae, infection on treatment; abnormal renal function, penicillin allergy
Interventions	Cephalothin 2 g IV within 1 hour of operation and at 4 and 8 hours after (N = 40) vs comparable appearing placebo (N = 40)
Outcomes	Febrile morbidity (oral temperature > 100.3°F twice 6 hours apart); infection of endometrium, urinary tract and wound (definitions not provided); fever index (40 degree hours for treatment group vs 83 for placebo group)
Notes	Class of antibiotic: first generation cephalosporin.
	Subgroups: non-elective CS; before cord clamping.
Risk of bias
Item	Authors’ judgement	Description
Adequate sequence generation?	Unclear	Selected in random …manner”. No further information provided.
Allocation concealment?	Unclear	No information provided.
Blinding?	Yes	Double blind, placebo controlled.
All outcomes		“The placebo was comparable to the cephalothin in both appearance and viscosity of solution.”
Incomplete outcome data addressed?	Unclear	No loss to follow up or exclusion of participants after randomization described, but results of only 80/85 participants reported Insufficient detail to know if the analysis was ITT.
All outcomes
Free of selective reporting?	Unclear	Insufficient information to judge.
Free of other bias?	Unclear	The 2 groups were comparable, but insufficient information overall
Overall low risk of bias?	Unclear	Mostly unclear.