Predictive value of Creasy's high risk factors score in prediction of threatened premature labor

Objective To discuss the predictive value of Creasy's high risk factors score in prediction of threatened premature labor,in order to improve precursor to the diagnosis of premature birth,decrease the rate of premature birth and improve the quality of birth. Methods We selected 532 pregnant women of 28-36⁺⁶ gestational weeks as the research objects from January 2016 to June 2016 in our hospital.All cases were analyzed with Creasy risk factor score.We used χ² test to compare Creasy risk factor's high risk scores between different gestational weeks,and the incidences of threatened premature labor were compared between with and without threatened premature labor in different gestational weeks by t test,to calculate the sensitivity,specificity,accuracy and positive predictive value of each score. Results Creasy's premature labor scores the highest between 9 to 12 points,accounting for 34.40% (183/542).A total of 127 cases suffered from threatened premature labor,with an incidence rate of 23.87%(127/532).When Creasy's high risk factors scores 12,the sum of sensitivity 88.97%(113/127) and specificity 83.95%(340/405) reaches the maximum.At the same time,the accuracy 85.15%(453/532) and positive predictive value 63.48%(113/178) are the highest.Therefore,we set ≥ 12 points as the critical value to predict threatened premature labor.The rate of pregnancy in patients with<12 Creasy's high risk factors score was 85.71%(12/14),higher than 76.11%(86/113) in those with ≥ 12 scores.The scores in threatened premature labor women were significantly higher than those without in different gestational weeks of 28-29⁺⁶(15.24±3.22 vs. 7.25±1.84,t=26.633,P<0.001),30-31⁺⁶(16.11±3.51 vs. 8.41±1.88,t=23.680,P<0.001),32-33⁺⁶(17.21±3.38 vs. 8.68±1.96,t=27.050,P<0.001) and 34-36⁺⁶(13.58±3.06 vs. 6.35±1.62,t=25.529,P<0.001). Conclusion Creasy risk factor score ≥ 12 may predict the occurrence of threatened premature labor effectively.Higher Creasy's high risk factors score leads to higher incidence of threatened premature labor and lower successful rate of pregnancy.