A cohort study found that white blood cell count and endocrine markers predicted preterm birth in symptomatic women

Objective: This cohort study investigated potential clinical and biochemical predictors of subsequent preterm birth in women presenting with threatened preterm labor. Study Design and Setting: Subjects were 218 pregnant women admitted to hospital with a diagnosis of threatened preterm labor at 22-36 weeks gestation. Exclusion criteria were multiple pregnancy, fetal anomalies, diabetes mellitus, abruptio placenta, preeclampsia, intrauterine growth restriction, cervical dilatation > 4 cm, and clinical signs of infection. Analyses used logistic regression. Results: The presence of ruptured membranes was the best predictor of birth within 48 hours. Other important predictors were maternal white blood cell count at 22-27 weeks gestation and maternal adrenocorticotropin and corticotropin-releasing hormone concentrations at 28-36 weeks gestation. Conclusion: Subclinical infection may be an important etiologic factor in preterm births of gestational age < 28 weeks. For those at greater than or equal to28 weeks gestation, the findings support the etiologic role of activation of the fetal and/or maternal hypothalamic pituitary adrenal axis leading to preterm birth. (C) 2005 Elsevier Inc. All rights reserved.