Murakawa H, Utumi T, Hasegawa I, Tanaka K, Fuzimori R
Department of Obstetrics and Gynecology, Akita Red Cross Hospital, Japan.
Obstet Gynecol. 1993 Nov;82(5):829-32.
To establish a nomogram for the length of the uterocervical canal and to determine whether this can be used to predict preterm delivery.
Cervical length was measured by transvaginal ultrasonography in 32 women (21 primigravid, 11 multigravid) with threatened preterm delivery, and in 177 normal singleton pregnancies between 18-37 weeks' gestation. Regression analysis was used to create the nomogram. Student t test was used to compare the groups.
A linear relationship was found between cervical length and gestational age (r = -0.4, P < .001). Comparison of cervical length on admission in the patients with threatened preterm delivery showed that 11 preterm deliveries occurred in women who had a mean cervical length of 23.2 mm (range 17-29), whereas 21 term deliveries occurred in women with a mean cervical length of 31.7 mm (range 21-42). The difference was significant (P < .001). A cervical length of less than 20 mm on admission had a positive predictive value of 100%. These patients had preterm delivery despite tocolytic therapy during hospitalization.
The risk of preterm delivery is high in women whose cervical length on admission is less than 30 mm, and strict management is required for those with a cervical length of less than 20 mm.
建立子宫颈管长度的列线图，并确定其是否可用于预测早产。
对32例有早产风险的孕妇（21例初产妇，11例经产妇）以及177例孕18 - 37周的正常单胎妊娠孕妇进行经阴道超声测量宫颈长度。采用回归分析创建列线图。用Student t检验比较各组。
发现宫颈长度与孕周之间存在线性关系（r = -0.4，P <.001）。对有早产风险的患者入院时的宫颈长度进行比较，结果显示，平均宫颈长度为23.2 mm（范围17 - 29）的孕妇中有11例发生早产，而平均宫颈长度为31.7 mm（范围21 - 42）的孕妇中有21例足月分娩。差异有统计学意义（P <.001）。入院时宫颈长度小于20 mm的阳性预测值为100%。这些患者尽管在住院期间接受了宫缩抑制治疗仍发生了早产。
入院时宫颈长度小于30 mm的女性早产风险高，宫颈长度小于20 mm的患者需要严格管理。
