Incidence, risk factors and outcomes of maternal sepsis in a Scottish region over 23 years

Summary

Severe sepsis is a potentially life-threatening condition, which is characterized by systemic inflammatory response syndrome (SIRS) with infection, organ dysfunction, hypoperfusion and hypotension. If untreated, this condition can rapidly progress along a continuum of severity to septicaemic shock and eventually death. Pregnant and postnatal women represent a particularly vulnerable population for developing severe sepsis due to changing physiology, biochemistry, and immune response, as well as heightened susceptibility to wound infection during delivery. Although death as a result of pregnancy related sepsis is uncommon in the United Kingdom (UK) and other high-income countries, mortality rates have more than doubled over the last two decades in the UK and have also increased in other European countries. However, there is very little information on corresponding trends in sepsis morbidity. The aim of this study was to describe the incidence, risk factors and outcomes of maternal sepsis using data from the Aberdeen Maternal and Neonatal Databank.

The results showed that, after controlling for mode of delivery and demographic and clinical factors, obese women had twice the odds of uncomplicated sepsis (OR=2.12, CI=1.14-3.89) compared to normal weight women. Age <25 (OR=5.15; CI=2.43-10.90) and operative vaginal delivery (OR=2.20; CI=1.02-4.87) were also significant predictors of sepsis. Known risk factors for maternal sepsis were also significant in this study (OR=uncomplicated and severe sepsis respectively): multiparity (OR=6.29, 12.04), anaemia (OR=3.43, 18.49), labour induction (OR=3.92 severe only), Caesarean section (OR=3.23, 13.35), and preterm birth (OR=2.46 uncomplicated only).

The association observed between operative vaginal delivery and maternal sepsis emphasises the importance of strict aseptic technique and infection control measures in clinical practice. The association between obesity and maternal sepsis is also of clinical significance given the concurrent increase in maternal obesity in the UK. This study, however, despite using a large population database, had limited power to investigate factors associated with severe maternal sepsis. We therefore suggest further research, including a national prospective cohort study, to comprehensively evaluate the magnitude of severe maternal sepsis morbidity, and to validate the risk factors identified in this study.