Risk factors in cesarean section infection.

Factors associated with risk of postoperative infection after cesarean section were studied in 321 patients not given antibiotic prophylaxis. Infections occurred in 56 (25%) of the 228 patients who were delivered by emergency cesarean section and in eight (9%) of the 93 patients who underwent elective surgery (P less than .01). These frequencies corresponded well with the infection rates reported after administration of antibiotics in other studies. Risk factors were: duration of operation more than one hour; blood loss more than 800 ml; presence of Staphylococcus aureus in the nares; signs of intrauterine infection before surgery; and failure of progress in labor. The results indicated that obstetric interventions had been performed more frequently in patients at risk of infection, rather than being the real cause of the infections. The importance of strict preoperative hygienic routine is discussed.