Complement, fetal antigen, and shaking rigors in parturients

Department of Obstetrics and Gynecology, Northwestern University, Evanston, Illinois, United States
Journal of Maternal-Fetal and Neonatal Medicine (Impact Factor: 1.37). 02/2006; 19(1):31-4. DOI: 10.1080/14767050500362206
Source: PubMed


To assess the relationship, if any, between complement, fetal antigen, and shaking rigors during labor and delivery.
We recruited 13 volunteers for serial blood sampling during labor and childbirth.
Complement levels had a small but significant drop (11-15%) immediately following childbirth but had no association with fetal antigen levels or shaking rigors. Fetal antigen levels failed to show any consistent relationship with shaking rigors or the labor and delivery process.
Shaking rigors do not appear to be associated with changes in either complement or fetal antigen levels. Complement levels remain stable during labor but drop immediately following birth.

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    • "C5a up-regulated pro-inflammatory and pro-labor mediators, including pro-inflammatory cytokines (IL-6 and IL-8), cyclooxygenase (COX)-2, PGE2 and PGF2α, matrix metalloproteinase (MMP)-9, and 8-isoprostane in human gestational tissues via the C5a receptor (CD88)-mediated NF-κB activation (Lappas et al., 2012). Abundant research has demonstrated complement activation in an innate immunity of human parturition (Gallery et al., 1981; Benson et al., 2006; Benson, 2007; Soto et al., 2009; Gonzalez et al., 2011; Kato et al., 2012; Lappas et al., 2012), but has yet to investigate whether complement activation is the result of fetal antigen leaking into the maternal circulation. "
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