Abstract：
BACKGROUND: Preterm birth (PTB) is a major pregnancy complication. There is evidence that a short cervical length in mid-pregnancy may predict women at increased risk of PTB.
OBJECTIVE: To evaluate the utility of population-based, transabdominal cervical length (TACL) measurement screening in mid-pregnancy for PTB prediction in women.
METHODS: A transabdominal approach was initially performed, with a transvaginal (TVCL) approach offered when the TACL was <35 mm, could not be accurately measured, or the pregnancy had risk factors for PTB. TACL was compared to the directly related TVCL, when both were performed at the same assessment. Women with risk factors of PTB were included when they had both TACL and TVCL measurements performed at the same visit.
RESULTS: Data were provided for 9355 singleton pregnancies from 13 participating imaging centres. A transabdominal approach was used in 9006 (96.3%), including 682 (7.3%) TVCL combined with TACL. There were 349 (3.7%) women who had TVCL only. The median TACL was longer (40 mm) than the TVCL (38 mm). In 682 paired TACL and TVCL measurements, TACL <35 mm correctly identified 96.2% of pregnancies with TVCL <25 mm, compared with 65.4% of cases when using a TACL <30 mm. A TVCL <25 mm occurred in 59 (0.6%) women. A TACL <35 mm was associated with birth <37 weeks of gestation in 12.1% of women and birth <32 weeks of gestation in 3.9%.
CONCLUSIONS: Universal TACL is a feasible option for population screening of cervical length in a low-risk population, progressing to TVCL if the TACL is <35 mm or the cervix cannot be transabdominally accurately measured.
OBJECTIVE: To evaluate the utility of population-based, transabdominal cervical length (TACL) measurement screening in mid-pregnancy for PTB prediction in women.
METHODS: A transabdominal approach was initially performed, with a transvaginal (TVCL) approach offered when the TACL was <35 mm, could not be accurately measured, or the pregnancy had risk factors for PTB. TACL was compared to the directly related TVCL, when both were performed at the same assessment. Women with risk factors of PTB were included when they had both TACL and TVCL measurements performed at the same visit.
RESULTS: Data were provided for 9355 singleton pregnancies from 13 participating imaging centres. A transabdominal approach was used in 9006 (96.3%), including 682 (7.3%) TVCL combined with TACL. There were 349 (3.7%) women who had TVCL only. The median TACL was longer (40 mm) than the TVCL (38 mm). In 682 paired TACL and TVCL measurements, TACL <35 mm correctly identified 96.2% of pregnancies with TVCL <25 mm, compared with 65.4% of cases when using a TACL <30 mm. A TVCL <25 mm occurred in 59 (0.6%) women. A TACL <35 mm was associated with birth <37 weeks of gestation in 12.1% of women and birth <32 weeks of gestation in 3.9%.
CONCLUSIONS: Universal TACL is a feasible option for population screening of cervical length in a low-risk population, progressing to TVCL if the TACL is <35 mm or the cervix cannot be transabdominally accurately measured.
摘要：
背景：早产（PTB）是主要的妊娠并发症。有证据表明，妊娠中期宫颈长度短可能会预测妇女患PTB的风险增加。
目的：为了评估基于人群的效用，妊娠中期经腹宫颈长度（TACL）测量筛查，用于女性PTB预测。
方法：最初是经腹入路，当TACL<35mm时，采用经阴道（TVCL）方法，无法准确测量，或妊娠有PTB的危险因素。将TACL与直接相关的TVCL进行比较，当两者都在相同的评估中进行时。具有PTB危险因素的女性在同一访视时进行了TACL和TVCL测量。
结果：提供了来自13个参与成像中心的9355例单胎妊娠的数据。9006(96.3%)采用经腹入路,包括682(7.3%)TVCL和TACL。349名（3.7%）女性仅患有TVCL。中位TACL(40mm)比TVCL(38mm)长。在682对TACL和TVCL测量中，TACL<35mm正确识别了96.2％的TVCL<25mm的妊娠，与使用TACL<30mm的病例相比，这一比例为65.4%。59名（0.6%）女性发生TVCL<25mm。在12.1％的妇女中，TACL<35mm与出生<37孕周有关，在3.9％的妇女中，出生<32孕周有关。
结论：通用TACL是低风险人群宫颈长度筛查的可行选择，如果TACL<35mm或宫颈不能经腹精确测量，则进展为TVCL。
目的：为了评估基于人群的效用，妊娠中期经腹宫颈长度（TACL）测量筛查，用于女性PTB预测。
方法：最初是经腹入路，当TACL<35mm时，采用经阴道（TVCL）方法，无法准确测量，或妊娠有PTB的危险因素。将TACL与直接相关的TVCL进行比较，当两者都在相同的评估中进行时。具有PTB危险因素的女性在同一访视时进行了TACL和TVCL测量。
结果：提供了来自13个参与成像中心的9355例单胎妊娠的数据。9006(96.3%)采用经腹入路,包括682(7.3%)TVCL和TACL。349名（3.7%）女性仅患有TVCL。中位TACL(40mm)比TVCL(38mm)长。在682对TACL和TVCL测量中，TACL<35mm正确识别了96.2％的TVCL<25mm的妊娠，与使用TACL<30mm的病例相比，这一比例为65.4%。59名（0.6%）女性发生TVCL<25mm。在12.1％的妇女中，TACL<35mm与出生<37孕周有关，在3.9％的妇女中，出生<32孕周有关。
结论：通用TACL是低风险人群宫颈长度筛查的可行选择，如果TACL<35mm或宫颈不能经腹精确测量，则进展为TVCL。
