Postpartum C-Reactive Protein: A limited value to detect infection or inflammation

During pregnancy the maternal immune system adjusts to preserve the foetoplacental unit. These adjustments lead to an increase in CRP, continuing into the postpartum. The objective of this study was to determineantepartal, peripartal and postpartal factors associated with an elevated CRP on the second postpartum day.

A retrospective quantitative, monocentric file analysis in which antepartal, peripartal and postpartal factors were collected from a convenience sample was performed. On the second day postpartum CRP was taken according to local protocol. Uni- and multi-variate analysis was performed to determine factors that are related to postpartum level of CRP. The total sample size consisted of 1400 patients.

Multiple regression analysis indicated 11 factors related to increased CRP on the second day postpartum: gestational age (p=0.002), maternal blood leukocyte count on day 2 postpartum (p<0.001), artificial rupture of the membranes (p<0.001), fever during labor (p<0.001), indwelling urinary catheter (p=0.008), epidural anesthesia (p<0.001), fetal scalp electrode (p<0.001), primary planned caesarean (p=0.019), secondary caesarean h (p<0.001), formula feeding (p=0.030) and fever during postpartum (p=0.001).

This research indicates that many antepartal, peripartal and postpartal factors are related to high postpartum CRP. CRP can not be used as a screening test test in the postpartum to discriminate between normal and pathologic inflammatory/infectious changes.