Risk Factors for Postcesarean Maternal Infection in a Trial of Extended-Spectrum Antibiotic Prophylaxis.
To identify maternal clinical risk factors for postcesarean maternal infection in a randomized clinical trial of preincision extended-spectrum antibiotic prophylaxis.



We conducted a planned secondary analysis of a randomized clinical trial. Patients were 24 weeks of gestation or greater and delivered by cesarean after a minimum of 4 hours of ruptured membranes or labor. All participants received standard preincision prophylaxis and were randomized to receive azithromycin or placebo. The primary outcome for this analysis is maternal infection: a composite outcome of endometritis, wound infection (superficial or deep), or other infections occurring up to 6 weeks postpartum. Maternal clinical characteristics associated with maternal infection, after controlling for azithromycin assignment, were identified. These maternal factors were included in a multivariable logistic regression model for maternal infection.



Of 2,013 patients, 1,019 were randomized to azithromycin. Overall, 177 (8.8%) had postcesarean maternal infection. In the final adjusted model, compared with the reference groups, women of black race-ethnicity, with a nontransverse uterine incision, with duration of membrane rupture greater than 6 hours, and surgery duration greater than 49 minutes, were associated higher odds of maternal infection (all with adjusted odds ratios [ORs] of approximately 2); azithromycin was associated with lower odds of maternal infection (adjusted OR 0.4, 95% confidence interval 0.3-0.6).



Despite preincision azithromycin-based extended-spectrum antibiotic prophylaxis, postcesarean maternal infection remains a significant source of morbidity. Recognition of risk factors may help guide innovative prevention strategies.



ClinicalTrials.gov, https://clinicaltrials.gov, NCT012235546.
University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; the University of Alabama at Birmingham, Birmingham, Alabama; the University of Texas Medical Branch, Galveston, Texas; Oshner Health System, New Orleans, Louisiana; the University of Utah and Intermountain Health-LC, Salt Lake City, Utah; Columbia University, New York, New York; Mission Hospital, Asheville, North Carolina; the University of Mississippi at Jackson, Jackson, Mississippi, the University of Houston at Houston, Houston, Texas; and WakeMed Physician Practices, Raleigh, North Carolina.
Kim A
KA
Boggess
Alan
A
Tita
Victoria
V
Jauk
George
G
Saade
Sherri
S
Longo
Erin A S
EAS
Clark
Sean
S
Esplin
Kristin
K
Cleary
Ronald
R
Wapner
Kelli
K
Letson
Michelle
M
Owens
Sean
S
Blackwell
Carmen
C
Beamon
Jeffrey M
JM
Szychowski
William
W
Andrews
D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D019072:Antibiotic Prophylaxis; D017963:Azithromycin / Q000627:therapeutic use*; D002585:Cesarean Section / Q000009:adverse effects*; D004359:Drug Therapy, Combination; D004716:Endometritis / Q000209:etiology / Q000517:prevention & control*; D005321:Extraembryonic Membranes; D005260:Female; D006801:Humans; D007743:Labor, Obstetric; D061646:Operative Time; D011184:Postoperative Period; D011247:Pregnancy; D012307:Risk Factors; D013530:Surgical Wound Infection / Q000209:etiology / Q000517:prevention & control*; D013997:Time Factors; D055815:Young Adult
D000900:Anti-Bacterial Agents; D017963:Azithromycin