ABSTRACT
Objective To determine the efficiency of cervical length by transvaginal sonography combined with serum relaxin for predicting premature birth.Methods The study enrolled 280 single births primipara.Cervical length was measured by transvaginal sonography during mid-trimester and late-trimester of pregnancy.Serum relaxin was measured during mid-trimester of pregnancy,late-trimester of pregnancy and postpartum.Sensitivity of cervical length,serum relaxin and cervical length combined with serum relaxin were applied for predicting premature birth.Results The sensitivity of cervical length and serum relaxin during mid-trimester of pregnancy for predicting premature birth were 54.43％ and 57.72％,respectively.The sensitivity of cervical length and serum relaxin during late-trimester of pregnancy for predicting premature birth was 62.74％ and 66.49％,respectively.Sensitivity of cervical length and serum relaxin during late-trimester of pregnancy for predicting preterm birth were more satisfying than those during mid-trimester of pregnancy.The sensitivity of cervical length combined with serum relaxin for predicting premature birth were 70.76％ and 71.51％,which were obviously higher than those obtained using cervical length or serum relaxin alone.Conclusion The combination of cervical length and serum relaxin can significantly improve the sensitivity of predicting premature birth,which can diagnose premature birth early and exactly.