OBJECTIVE: To investigate whether biomarkers from different pathways of spontaneous preterm birth (cervical membrane degradation [fetal fibronectin], cervical remodeling [soluble E-cadherin], and inflammation (elafin, surfactant protein-D, interleukin-6 [IL-6]) were superior to one biomarker alone in predicting preterm birth. Our secondary objective was to examine the association of these biomarkers with cervical length in predicting preterm birth.
METHODS: We performed a single-center, prospective cohort study from August 2011 to November 2012 of asymptomatic women at risk for spontaneous preterm birth as a result of obstetric and gynecologic history. Cervicovaginal fluid and cervical length measurements were collected at two time points (20–23 6/7 weeks and 24–27 6/7 weeks of gestation).
RESULTS: Among the 104 women with complete data, the preterm birth rate was 24.5%. Prior preterm birth (P=.006) and cervical length at visit 1 (P=.003) were significantly associated with preterm birth, whereas fetal fibronectin and median biomarker levels (elafin, soluble E-cadherin, IL-6) were not. Median surfactant protein-D levels at visit 1 by preterm birth status were statistically but not clinically different (0.44 ng/mL compared with 0.40 ng/mL, P<.001). Analyses of biomarkers from more than one pathway were not superior to single biomarker analyses in predicting prematurity. Neither inclusion of biomarkers nor fetal fibronectin improved the predictive ability of cervical length alone.
CONCLUSION: Cervical length assessment and obstetric history but not fetal fibronectin or biomarkers were useful in the risk stratification of women identified to be at greatest risk for spontaneous preterm birth.
LEVEL OF EVIDENCE: II
The ability to use cervical length to risk-stratify asymptomatic women at risk for spontaneous preterm birth is not improved by fetal fibronectin or other cervicovaginal biomarkers.
Maternal and Child Health Research Program, Department of Obstetrics & Gynecology, Center for Research on Reproduction and Women's Health, University of Pennsylvania, Perelman School of Medicine, Philadelphia, Pennsylvania.
Corresponding author: Jamie A. Bastek, MD, MSCE, Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Hospital of the University of Pennsylvania, 3400 Spruce Street, 585 Dulles Building, Philadelphia, PA 19104; e-mail: email@example.com.
Supported by the 2011–2012 American College of Obstetricians and Gynecologists/Hologic Research Award in Preterm Birth (J.A.B., principal investigator).
Financial Disclosure The authors did not report any potential conflicts of interest.
Presented at the Society for Maternal-Fetal Medicine Annual Meeting, February 11–16, 2013, San Francisco, California, and at the Society for Gynecologic Investigation Annual Meeting, March 20–23, 2013, Orlando, Florida.