Maternal serum C-reactive protein concentrations in early pregnancy and subsequent risk of preterm delivery

OBJECTIVE: To examine the relation between maternal early pregnancy serum C-reactive protein (CRP) and preterm delivery (PTD).

DESIGN AND METHODS: Women were recruited before 20 weeks gestation and were followed up until delivery. Maternal serum C-reactive protein CRP was measured by competitive immunoassay . Logistic regression procedures were used to calculate adjusted odds ratio (OR) and 95% confidence intervals (95%CI).

RESULTS: Elevations in CRP ( concentrations were associated with the risk of PTD overall. After adjusting for confounding, the OR for highest quartile (> or = 7.5 vs. < 2.0 mg/L) of C-reactive protein ( was 2.04 (95%CI: 1.13-3.69). Stratified analyses indicated that elevated CRP was associated with an increased risk of spontaneous preterm labour (OR=2.15, 95%CI: 0.85-5.42), medically indicated preterm delivery (OR=3.29, 95%CI: 0.98-11.02), and very preterm delivery (OR=20.6, 95%CI: 2.53-168.03), but not with preterm premature rupture of membranes (OR=1.48, 95%CI: 0.56-3.86).

CONCLUSIONS: Elevated C-reactive protein ( concentrations in early pregnancy are associated with an increased risk of PTD, particularly medically indicated PTD and very PTD.

Department of Preventive and Social Medicine, Faculty of Medicine, Chulalongkorn University , Bangkok