Souka A P, Heath V, Flint S, Sevastopoulou I, Nicolaides K H
Harris Birthright Research Centre for Fetal Medicine, King's College Hospital Medical School, London, United Kingdom.
Obstet Gynecol. 1999 Sep;94(3):450-4. doi: 10.1016/s0029-7844(99)00277-x.
To establish the relationship between cervical length at 23 weeks' gestation in twin pregnancies and risk of spontaneous preterm delivery.
Cervical length was measured during routine antenatal care by transvaginal sonography at 23 (range 22-24) weeks' gestation in 215 twin pregnancies. Distribution of cervical length was determined, and sensitivity and false-positive rate for spontaneous preterm delivery at or before 28, 30, 32, and 34 weeks for cutoff cervical lengths of 15, 25, 35, and 45 mm were calculated.
Cervical length distribution was skewed toward shorter length and the median value was 38 mm. In 11.2% and 4.2% of cases, length was up to 25 mm and up to 15 mm, respectively. The spontaneous delivery rates at or before 28, 30, 32, and 34 weeks were 3.8%, 4.7%, 8.0%, and 17.5%, respectively, and were not statistically significantly related to any demographic characteristics, obstetric history, or chorionicity. Sensitivity to predict spontaneous preterm delivery was 100%, 80%, 47%, and 35% for 28, 30, 32, and 34 weeks, respectively, for cervical length up to 25 mm. The corresponding sensitivity values for cervical lengths up to 15 mm were 50%, 40%, 24%, and 11%. The rate of spontaneous delivery at or before 32 weeks increased exponentially with decreasing cervical length at 23 weeks, from 2.9% at or greater than 46 mm, to 4.3% at 36-45 mm, 6.7% at 26-35 mm, 31% at 16-25 mm, and 66% at 15 mm or less.
Measurement of cervical length in twin pregnancies predicted risk of spontaneous early preterm delivery.
建立双胎妊娠孕23周时宫颈长度与自然早产风险之间的关系。
对215例双胎妊娠孕妇在孕23周（范围22 - 24周）进行常规产前检查时，经阴道超声测量宫颈长度。确定宫颈长度的分布情况，并计算宫颈长度截断值为15、25、35和45 mm时，孕28、30、32和34周及以前自然早产的敏感度和假阳性率。
宫颈长度分布呈向较短长度偏态分布，中位数为38 mm。分别有11.2%和4.2%的病例宫颈长度≤25 mm和≤15 mm。孕28、30、32和34周及以前的自然分娩率分别为3.8%、4.7%、8.0%和17.5%，且与任何人口统计学特征、产科病史或绒毛膜性均无统计学显著相关性。对于宫颈长度≤25 mm，预测自然早产的敏感度在孕28、30、32和34周时分别为100%、80%、47%和35%。对于宫颈长度≤15 mm，相应的敏感度值分别为50%、40%、24%和11%。孕32周及以前的自然分娩率随孕23周时宫颈长度的缩短呈指数增加，从宫颈长度≥46 mm时的2.9%，到36 - 45 mm时的4.3%，26 - 35 mm时的6.7%，16 - 25 mm时的31%，以及≤15 mm时的66%。
双胎妊娠中测量宫颈长度可预测自然早期早产风险。
