Cesarean section is the common surgery in world wide. But the complication like febrile morbidity such as surgical site infection, fever, urinary tract infection and endometritis can be occurred even giving the standard antibiotics. Therefore if wider bacterial spectrum coverage antibiotic like azithromycin is added to the standard antimicrobial prophylaxis(1st generation cephalosporin), the incidence of febrile morbidity could be reduced. We will compare the regimen of cefazolin plus azithromycin and standard regimen of cefazolin alone in prevention of febrile morbidity after emergency cesarean section.

This study was designed to evaluate the effect of azithromycin on the incidence of febrile morbidity after the emergency cesarean section. The standard antimicrobial prophylaxis which is recommended by the ACOG is the 1st generation cephalosporin intravenously only but some of the bacteria that can cause the febrile morbidity after cesarean section wouldn't be killed by the 1st generation cephalosporin. The antibiotic that can cover them is macrolide group antibiotic such as azithromycin. Therefore this study will compare the regimen of standard antimicrobial prophylaxis and the regimen of standard antimicrobial prophylaxis with azithromycin intravenously in preventing the febrile morbidity after emergency cesarean section. Control group will receive the 1st generation cephalosporin intravenously and the intervention group will receive the 1st generation cephalosporin with azithromycin 500mg intravenously. Primary outcome is febrile morbidity which assessed at postoperative day 3. The definition of the febrile morbidity in this study is including surgical site infection, endometritis, urinary tract infection and fever alone. Secondary outcomes are febrile morbidity at postoperative day 7 and day30, neonatal outcome and adverse effect from azithromycin use.

Inclusion Criteria:

1. Singleton pregnancy with a gestation of 24 weeks or more
2. Undergoing non-elective cesarean delivery during labor or rupture of membrane more than 4 hr
3. No allergy to macrolide such as azithromycin and clindamycin
4. Provide informed consent
5. Partner of participant allows the patient to participate the research

Exclusion Criteria:

1. Use of azithromycin within 7 days before enrollment
2. Chorioamnionitis or other infection requiring postpartum antibiotic therapy (except for antibiotics for group B streptococcus)
3. Liver disease (Cirrhosis or AST more than 3 times the upper normal limit)
4. Serum creatinine level of more than 2.0 mg/dL or need dialysis
5. Diarrhea at the time of enrollment
6. Maternal heart disease
7. Use of medication known to prolonged the QT interval

for singleton pregnant