Abstract: Objective：To assess the efficacy of cervical phosphorylated insulin-like growth factor binding protein-1（phIGFBP-1） in combination with cervical index measurement for the prediction of the diagnosis-delivery interval（DDI） for preterm delivery. Methods：A total of 188 threatened premature delivery women complaining with uterine contractions were recruited in this study，who received cervical swabs for phIGFBP-1 detection and transperineal ultrasound scan to assess cervical index. According to these results，all the patients are divided into three groups：double-positive group，one-positive group， double-negative group，they were followed until delivery. An analysis of the DDI between groups was carried out. Results：The DDI of double-positive group was shorter than that of double-negative group and one-positive group（P＜0.05）. When combining the two methods in forecasting DDI within one week，the values of the sensitivity，specificity，the positive predictive value and the negative predictive value were 100.0%（33/33），30.3%（47/155），65.0%（26/40），100.0%（47/47） respectively. In double-positive group，all the patients deliveried within one week and 85.7% of them deliveried within 48 hours when their cervical index were more than 0.8. The negative predictive value of double-negative group for delivery within two weeks was 100%（47/47）. Conclusions：The combination of cervical phIGFBP-1 and cervical index measurement may serve as an objective indication for the prediction of the DDI for premature delivery，and as a guide for clinical treatment.

Key words: Insulin-like growth factor binding protein-1, Uterine cervix, Premature delivery, Forcasting, Ultrasonography