Elevated C-reactive protein and complement C3 levels are associated with preterm birth: a nested case–control study in Chinese women

Abstract

Abstract Background Currently, there are many studies researched the associations between maternal serum inflammatory indicators (i.e. ferritin, C-reactive protein [CRP], C3 and C4) and preterm birth (PTB). The results, however, are inconsistent. Therefore, the aim of this study was to estimate the relationship between maternal serum inflammatory indicators and PTB in a nested case-control (NCC)study. Methods A NCC study was conducted by Guangxi Birth Cohort Study which enrolled a total of 6203 pregnant women between 50/7 and 346/7 weeks of gestational age (wGA) from six cities in China between 2015 and 2016. There were 206women who delivered preterm ( 16.60 mg/L) are related to the risk of PTB (OR = 2.16, 95% CI: 1.02–4.56, p = 0.044) in the first trimester. The association of C3 was extremely related to those who delivered PTB (OR = 2.53, 95% CI: 1.14–5.64, p = 0.023) in the first trimester. Moreover, no significant associations were found in C4 (p = 0.079) and ferritin (p = 0.067) between PTB. Conclusions Elevated concentrations of CRP and C3 in the first trimester were associated with increased risk of PTB. Inflammatory indicators may act a pivotal part in early diagnosis and prognosis of PTB.

Keywords

• C-reactive protein
• Complement C3
• Preterm birth
• First trimester
• Nested case-control study