Skentou C, Souka A P, To M S, Liao A W, Nicolaides K H
Harris Birthright Research Centre for Fetal Medicine, King's College Hospital Medical School, London, UK.
Ultrasound Obstet Gynecol. 2001 Jan;17(1):7-10. doi: 10.1046/j.1469-0705.2001.00357.x.
To establish the relation between cervical length at 23 weeks of gestation in twin pregnancies and risk of spontaneous delivery before 33 weeks.
Cervical length was measured by transvaginal sonography at 23 (range 22-24) weeks of gestation in 464 twin pregnancies attending for routine antenatal care. In the patients who were managed expectantly the relation between cervical length and the rate of spontaneous delivery before 33 weeks was determined.
The cervical length distribution was skewed to the left and the median value was 36 mm. The rate of spontaneous delivery before 33 weeks was inversely related to cervical length at 23 weeks. It increased gradually from about 2.5% at 60 mm, to 5% at 40 mm and 12% at 25 mm, and exponentially below this length to 17% at 20 mm and 80% at 8 mm. Cervical length of 20 mm or less is found in about 8% of the population and this group contained about 40% of women delivering spontaneously before 33 weeks.
In twin pregnancies measurement of cervical length provides useful prediction of risk for spontaneous early preterm delivery.
建立双胎妊娠孕23周时宫颈长度与33周前自然分娩风险之间的关系。
对464例接受常规产前检查的双胎妊娠孕妇在孕23周（范围22 - 24周）时经阴道超声测量宫颈长度。对于采取期待治疗的患者，确定宫颈长度与33周前自然分娩率之间的关系。
宫颈长度分布呈左偏态，中位数为36毫米。33周前自然分娩率与孕23周时的宫颈长度呈负相关。从60毫米时的约2.5%逐渐增加到40毫米时的5%和25毫米时的12%，在该长度以下呈指数增加，20毫米时为17%，8毫米时为80%。约8%的人群宫颈长度为20毫米或更短，该组中约40%的女性在33周前自然分娩。
在双胎妊娠中，测量宫颈长度可为早期自然早产风险提供有用的预测。
