ABSTRACT
Objective To compare three ultrasonic methods of transabdominal , transvaginal , and transperineal ultrasonogra-phy for the cervical length ( CL) in predicting the preterm birth .Methods The pregnancy women with threatened preterm labor in Hunan Provincial Hospital of Maternal and Child Health from January , 2012 to December, 2013 were chosen to measure the cervical length by sonography , and were randomly divided into three guoups ( 280 pregnancy women in each group ) , including Group Ⅰ( transabdominal ) , groupⅡ( transvaginal ) , and group Ⅲ ( transperineal ) .The cervical length and the pregnancy outcome were fol-lowed up.Results The acceptance rate of group Ⅱ(81.8%=229/280) was significantly lower than that of groupⅠ(100%=280/280)and group Ⅲ(99.3%=278/280)( P <0.05).The realization ratio of the cervix in group Ⅰ(85.0%=238/280) was signifi-cantly lower than that of group Ⅱ(98.7%=226/229) and group Ⅲ (98.2%=273/278) ( P <0.05).The preterm birth rate of 48.6%(18/37) in groupⅠ, 37.8%(28/74) in groupⅡ, and 37.1%(33/89) in groupⅢin the pregnancy women with CL <3 cm was significantly higher than the corresponding preterm birth rate of 17.9%(36/201) in groupⅠ, 13.2%(20/152)in groupⅡ, and 13.6% (25/184) in groupⅢin the pregnancy women with CL≥3 cm.The sensitivity of groupⅠ(33.3%=18/54) was significantly lower than that of group Ⅱ(58.3%=28/48) and group Ⅲ(56.9%=33/58).Conclusions The cervical length measured by ultra-sound is valuable in predicting preterm birth among the pregnancy women with threatened preterm birth .The transperineal ultrasonogra-phy is superior to transabdominal and transvaginal ultrasonography in predicting preterm birth , and is worth being popularized .