Preterm delivery at low gestational age: risk factors for short latency. A multivariated analysis.

OBJECTIVE: The aim of this study is to identify the risk factors for a short latency in preterm delivery at low gestational ages (GA). STUDY DESIGN: A retrospective analysis involving, between January 2004 and May 2006, 204 singleton pregnancies with admission diagnosis of preterm labor and, in particular, 91 pregnant women admitted between 24+0 and 31+6 weeks' gestation. RESULTS: In pregnant women with a diagnosis of preterm labor at 24-31+6 weeks' gestation, at ROC curve, a value of considering WBC and cervical dilatation, combined in the following formula (75.237 - (2.290 * "WBC") - (10.787 * "cervical dilatation")) <=33.101 has a 74.2% Sensitivity and a 78.3% Specificity in predicting a latency =< 4 days (+LR 3.42 and -LR 0.33) and a 70% Sensitivity and a 84.3% Specificity in predicting GA at delivery at 24-31 weeks' gestation (+LR 4.46 and -LR 0.36). CONCLUSION: We suggest a more strictly monitoring and a more aggressive therapy in presence of prognostic parameters of shorter latency.