A Randomized Trial to Investigate if a Pre-operative Wash With Chlorhexidine vs Povidone-iodine Vaginal Scrub Decreases Infectious Morbidity in Patients Undergoing Cesarean Section After Ruptured Membranes

Postpartum endometritis is an infection of the endometrial lining of the uterus clinically diagnosed by fever and uterine fundal tenderness. The most important risk factor for developing endometritis is cesarean section, as it occurs in 11% of cesarean sections after labor and 3% of elective cesarean sections. Other risk factors for endometritis are chorioamnionitis, prolonged labor, prolonged rupture of membranes and vaginal colonization with Group B Streptococcus. Some complications of endometritis include prolonged hospital stay, sepsis, peritonitis and intrapelvic abscess.

Surgical site infections are infections of the incision, organ or space after a procedure and are responsible for 38% of infections in patients undergoing surgery. In obstetric patients, infectious morbidity (wound complication, surgical site infections, endometritis) occurs in 5-10% of cesarean sections, which is 5-fold higher than vaginal deliveries. Additionally, infectious morbidity is thought to be highest in those patients who have cesarean sections after undergoing labor.

Current practices endorsed by ACOG and the CDC to reduce the incidence of infectious morbidity after cesarean section include pre-operative antibiotics and pre-operative skin cleansing with chlorhexidine skin preparation. Chlorhexidine and povidone-iodine are chemical antiseptics that reduces bacteria found on the skin. Additionally, vaginal scrub with 4% chlorhexidine gluconate and 10% povidone-iodine antiseptic solution immediately prior to cesarean section has been embraced into some practices as a means to decrease infectious morbidity. There is abundant literature showing pre-operative vaginal cleansing prior to hysterectomy has been shown to decrease vaginal surgical site antisepsis, however research on its use prior to cesarean section is limited.

This study aims to assess the effectiveness of pre-operative vaginal scrub with 4% chlorhexidine or 10% povidone iodine in reducing infectious morbidity (specifically endometritis and SSI) in patients undergoing cesarean section with previously ruptured membranes. Current standard of care is use of pre-operative vaginal scrub with 10% povidone iodine. Patients will be randomized to one of two groups using pre-operative vaginal scrub for 30 seconds: 4% chlorhexidine or 10% povidone iodine. In addition both groups will receive pre-operative antibiotics with cefazolin and azithromycin, as well as abdominal cleansing with chlorhexidine-alcohol based skin preparation and 0.25% chlorhexidine wipe for 30 seconds, as this is standard of care for women undergoing cesarean section with ruptured membranes. In the event of penicillin allergy, antibiotics are adjusted accordingly.