. Author manuscript; available in PMC: 2007 Sep 27.

Published in final edited form as: Am J Epidemiol. 2005 Oct 19;162(11):1108–1113. doi: 10.1093/aje/kwi323

TABLE 1.

Association between elevated plasma C-reactive protein concentrations and preterm delivery^* according to multivariate conditional logistic regression analysis, Project Viva, Massachusetts, 1999–2003

C-reactive protein concentration	All cases (n = 117)		Spontaneous delivery (n = 55 cases)		Indicated delivery (n = 61 cases)
C-reactive protein concentration	Odds ratio	95% confidence interval	Odds ratio	95% confidence interval	Odds ratio	95% confidence interval
≥8 vs. <8 mg/liter^†
Adjusted for gestational age at blood collection^‡	2.76	1.23, 6.21	4.70	0.99, 22.37	1.64	0.58, 4.59
Multivariate adjusted^§	2.55	1.05, 6.20	4.64	0.94, 22.96	1.42	0.44, 4.61
≥12 vs. <12 mg/liter^†
Adjusted for gestational age at blood collection^‡	2.95	1.05, 8.33	7.50	0.89, 62.95	1.29	0.34, 4.88
Multivariate adjusted^§	3.19	0.98, 10.32	7.24	0.85, 61.53	1.39	0.28, 7.02

For one case, information on type of delivery was missing.

^†

A threshold value of 8 mg/liter corresponded to the 90th percentile, and 12 mg/liter corresponded to the 94th percentile in the control group.

^‡

Controlled for matching factors of age, race/ethnicity, and cigarette smoking.

^§

Controlled for matching factors of age, race/ethnicity, and cigarette smoking; additionally adjusted for gestational age at blood collection and prepregnancy body mass index.