PARK CITY, UTAH – The risk of sepsis after delivery persists beyond 6 weeks, the traditional point at which women are thought to be in the clear, according to investigators from Stanford (Calif.) University.
The team analyzed 506 sepsis hospitalizations following delivery, culled from almost 2 million live births in California from 2008-2012; 199 (39%) were at or before 6 weeks postpartum, and 310 (61%) were after 6 weeks, out to a year.
“Going into this, our view was that sepsis cases before 6 weeks would be due to obstetrical causes, and cases after 6 weeks would be due to [nonobstetrical causes],” said senior investigator Ronald Gibbs, MD, clinical professor of obstetrics and gynecology at Stanford. But that’s not what the team found.
In both the early and late admission groups, early preterm delivery was one of the leading risks for postpartum sepsis and other risk factors were largely the same. Pyelonephritis and pneumonia were by far the most common diagnoses in both groups, accounting for more than 70% of cases. The rank order of causative organisms was the same whether women presented before 6 weeks or after: gram-negative bacteria, staphylococcus, and streptococcus.
“In view of this, we think the risk for sepsis goes beyond 6 weeks,” Dr. Gibbs said at the annual scientific meeting of the Infectious Diseases Society for Obstetrics and Gynecology. Although women were admitted largely for nonuterine infections, “the reservoir of infection could be in the uterus,” with later seeding to the urinary tract or lungs. “I think there’s a chronic intrauterine infection that sets women up for” both early preterm birth and later sepsis, he added.
“These late admissions would probably go to a nonobstetrical service, but we are thinking that there may be a pelvic origin related to something that went on at delivery. I can’t really say that we ought to change our practice, but it sets the stage for looking at that. Finding that late [admissions for sepsis] have a lot in common with the early admissions and are probably related to the pregnancy really reorders the thinking,” Dr. Gibbs said.
The team found that among women who were delivered at 24-28 weeks, the adjusted odds ratio was 8.6 (95% confidence interval[CI], 4.4-17.1) for early and 4.2 (95% CI, 1.9-9.0) for late postpartum sepsis admission, even after delivery mode, maternal comorbidities, maternal age, “and everything else we could think of” were controlled for, said lead investigator, a maternal-fetal medicine fellow at Stanford.
A body mass index above 35 kg/m2 also increased the risk for sepsis admission, as did government-provided insurance, primary cesarean delivery, a failed trial of labor after a previous cesarean, and four or more previous deliveries.
Postoperative infection, acute hepatic failure, acute renal failure, acute respiratory failure, and heart failure during the delivery hospitalization greatly increased the risk of subsequent sepsis, as well.
The findings help define a group of women who likely need especially close follow-up after delivery to prevent sepsis, Dr. Foeller said.
Sepsis was defined in the study by ICD-9 codes for septicemia plus acute organ dysfunction.
There was no industry funding for the work and the investigators reported having no relevant financial disclosures.