Procalcitonin Reference Values Established for Term Pregnancy and Early Postpartum
A prospective cross-sectional study of 189 healthy pregnant women defined reference intervals for CRP and procalcitonin at term and postpartum. The maximum procalcitonin at term pregnancy was 0.1 microg/L, and 86-90% of day-1 postpartum values remained below the standard 0.25 microg/L decision threshold regardless of delivery mode. The 0.25 microg/L cutoff achieved 91.5% specificity for ruling out infection, establishing procalcitonin as a more reliable sepsis marker than CRP during pregnancy, where CRP variability limits clinical utility.
The original study
Reference values for C-reactive protein and procalcitonin at term pregnancy and in the early postnatal period.
- Authors
- Joyce CM, Deasy S, Abu H, Lim YY, O'Shea PM, O'Donoghue K
- Journal
- Annals of clinical biochemistry
- Type
- Clinical Trial, Journal Article
- PMID
- 33730872
Original abstract
BACKGROUND: Early recognition of sepsis and prompt treatment improves patient outcome. C-reactive protein is a sensitive marker for tissue damage and inflammation, but procalcitonin has greater specificity for bacterial infection. Limited research exists regarding the use of C-reactive protein and procalcitonin at term pregnancy and the immediate postpartum period. AIM: This study sought to define reference values for C-reactive protein and procalcitonin at term and the early postnatal period. METHODS: A prospective cross-sectional study was performed in a university teaching hospital. Venous blood was collected from healthy women (n = 196), aged between 19 and 45 years with an uncomplicated singleton pregnancy, at term (37-40 weeks' gestation) and on day 1 and day 3 postpartum for the measurement of C-reactive protein and procalcitonin. RESULTS: The reference population comprised of 189 participants: term pregnancy (n = 51), postpartum day 1 vaginal delivery (n = 70) and caesarean section (n = 38) and day 3 (caesarean section, n = 30). The maximum procalcitonin value at term pregnancy was 0.1 μg/L. On day 1 postpartum, 90% and 86.8% of procalcitonin results for vaginal delivery and caesarean section, respectively, were below the decision-threshold of 0.25 μg/L. The specificity of procalcitonin to rule out infection in the reference population was 91.5%. CONCLUSIONS: Reference values for procalcitonin were established in a well-characterized population of healthy pregnant women at term and immediately postpartum. The variability of C-reactive protein limits its clinical utility in the assessment of systemic sepsis. Application of the procalcitonin cut-off of 0.25 μg/L in this population will be a valuable adjunct to clinicians ruling out infection in pregnancy and postpartum.