OBJECTIVES: To determine the antecedents, outcomes, and effects of treatment of fever commencing during term labour without prolonged rupture of membranes (ROM). METHODS: A retrospective database and chart review sought associations between maternal, fetal, and labour variables and fever by comparing women whose membranes had been ruptured for less than 24 hours and who were febrile with those who were not. The strength of significant associations was then compared between febrile women who received acetaminophen or antibiotics and febrile women who did not. RESULTS: We found 16 322 control subjects and 161 cases. On multivariable analysis, fever was associated with epidural analgesia (adjusted odds ratio [AOR] 5.5; 95% confidence interval [CI], 4.0-7.0), length of stage 2 (AOR 1.003 per minute; 95% CI, 1.001-1.005), length of ROM (AOR 1.15 per hour; 95% CI, 1.10-1.20), meconium in the amniotic fluid (AOR 1.7; 95% CI, 1.2-2.2), intervention for nonreassuring electronic fetal monitoring (EFM) (AOR 5.2; 95% CI, 4.4-6.0), intervention for failure to progress in labour (AOR 3.0; 95% CI, 2.1-3.9), and neonatal intensive care unit (NICU) admission (AOR 5.7; 95% CI, 5.1-6.3). A nonstatistically significant trend toward a decrease in failure to progress with acetaminophen administration was noted. CONCLUSIONS: Fever during labour is associated with longer labour, longer ROM, and use of epidural analgesia. For a given length of labour, women with fever are more likely to experience intervention for failure to progress, intervention for nonreassuring EFM, and infant NICU admission.