Fetal fibronectin, interleukin-6, and C-reactive protein are useful in establishing prognostic subcategories of idiopathic preterm labor.
OBJECTIVE
Our purpose was to evaluate fetal fibronectin, interleukin-6, and C-reactive protein from patients with preterm labor to establish prognostic subcategories.


METHODS
Thirty-seven patients with preterm labor had cervical fetal fibronectin and plasma C-reactive protein sampled. Eighteen of these patients had amniotic fluid interleukin-6 levels measured. Outcome variables were (1) delivery before 34 weeks and (2) delivery within 48 hours.


RESULTS
Detectable cervical fetal fibronectin identified 89% of patients who were delivered before 34 weeks' gestation. Interleukin-6 > 1500 pg/ml identified 88% of patients who were delivered within 48 hours. C-reactive protein > 1.5 mg/dl correlated with elevated interleukin-6 levels (p < 0.001).


CONCLUSIONS
Three subcategories of idiopathic preterm labor were evident: (1) fetal fibronectin nondetectable (37% likely to be delivered before 34 weeks), (2) fetal fibronectin detectable but interleukin-6 < 1500 pg/ml (79% likely to be delivered before 34 weeks but 85% with > 48 hours' latency), and (3) fetal fibronectin present and interleukin-6 > 1500 pg/ml (91% likely to be delivered with < 48 hours' latency).
D000653:Amniotic Fluid / Q000276:immunology; D015415:Biomarkers / Q000032:analysis; D002097:C-Reactive Protein / Q000032:analysis*; D002584:Cervix Uteri / Q000737:chemistry; D016009:Chi-Square Distribution; D005260:Female; D005333:Fetus / Q000378:metabolism*; D005353:Fibronectins / Q000032:analysis*; D006801:Humans; D015850:Interleukin-6 / Q000032:analysis*; D007752:Obstetric Labor, Premature / Q000175:diagnosis* / Q000276:immunology / Q000378:metabolism; D011247:Pregnancy; D011379:Prognosis
D015415:Biomarkers; D005353:Fibronectins; D015850:Interleukin-6; D002097:C-Reactive Protein