Esplin M Sean, Elovitz Michal A, Iams Jay D, Parker Corette B, Wapner Ronald J, Grobman William A, Simhan Hyagriv N, Wing Deborah A, Haas David M, Silver Robert M, Hoffman Matthew K, Peaceman Alan M, Caritis Steve N, Parry Samuel, Wadhwa Pathik, Foroud Tatiana, Mercer Brian M, Hunter Shannon M, Saade George R, Reddy Uma M
Intermountain Healthcare, Salt Lake City, Utah2University of Utah Health Sciences Center, Salt Lake City.
University of Pennsylvania, Philadelphia.
JAMA. 2017 Mar 14;317(10):1047-1056. doi: 10.1001/jama.2017.1373.
Spontaneous preterm birth is a leading cause of infant mortality. Prediction, largely based on prior pregnancy outcomes, is not possible in women pregnant for the first time.
To assess the accuracy of universal screening to predict spontaneous preterm birth in nulliparous women using serial measurements of vaginal fetal fibronectin levels and cervical length.
DESIGN, SETTINGS, AND PARTICIPANTS: A prospective observational cohort study of nulliparous women with singleton pregnancies, from 8 clinical sites across the United States between October 2010 and May 2014. Women and clinicians were blinded to results unless cervical shortening less than 15 mm was identified.
Transvaginal cervical length and quantitative vaginal fetal fibronectin levels were reviewed at 2 study visits 4 or more weeks apart.
Spontaneous preterm birth at less than 37 weeks was the primary outcome. Cervical length and quantitative fetal fibronectin were considered independently and together at each visit. Measurement distributions were compared for spontaneous preterm birth vs all other births. Spontaneous preterm birth before 32 weeks was a secondary outcome.
The study included 9410 women (median age, 27.0 [interquartile range, 9.0] years; 60.7% non-Hispanic white, 13.8% non-Hispanic black, 16.5% Hispanic, 4.0% Asian, and 5.1% other), of whom 474 (5.0%) had spontaneous preterm births, 335 (3.6%) had medically indicated preterm births, and 8601 (91.4%) had term births. Among women with spontaneous preterm birth, cervical length of 25 mm or less occurred in 35 of 439 (8.0%) at 16 to 22 weeks' gestation and in 94 of 403 (23.3%) at 22 to 30 weeks' gestation. Fetal fibronectin levels of 50 ng/mL or greater at 16 to 22 weeks identified 30 of 410 women (7.3%) with spontaneous preterm birth and 31 of 384 (8.1%) at 22 to 30 weeks. The area under the receiver operating characteristic curve for screening between 22 and 30 weeks for fetal fibronectin level alone was 0.59 (95% CI, 0.56-0.62), for transvaginal cervical length alone was 0.67 (95% CI, 0.64-0.70), and for the combination as continuous variables was 0.67 (95% CI, 0.64-0.70).
Among nulliparous women with singleton pregnancies, quantitative vaginal fetal fibronectin and serial transvaginal ultrasound cervical length had low predictive accuracy for spontaneous preterm birth. These findings do not support routine use of these tests in such women.
自发性早产是婴儿死亡的主要原因。由于主要基于既往妊娠结局进行预测，所以首次怀孕的女性无法进行预测。
通过连续测量阴道胎儿纤维连接蛋白水平和宫颈长度，评估通用筛查对预测初产妇自发性早产的准确性。
设计、地点和参与者：一项前瞻性观察性队列研究，研究对象为2010年10月至2014年5月期间来自美国8个临床地点的单胎初产妇。除非发现宫颈缩短小于15毫米，否则女性和临床医生对结果均不知情。
在相隔4周或更长时间的2次研究访视中，对经阴道宫颈长度和定量阴道胎儿纤维连接蛋白水平进行评估。
妊娠小于37周的自发性早产是主要结局。每次访视时分别单独以及综合考虑宫颈长度和定量胎儿纤维连接蛋白。比较自发性早产与所有其他分娩的测量分布情况。妊娠32周前的自发性早产是次要结局。
该研究纳入了9410名女性（中位年龄27.0岁[四分位间距9.0岁]；60.7%为非西班牙裔白人，13.8%为非西班牙裔黑人，16.5%为西班牙裔，4.0%为亚洲人，5.1%为其他种族），其中474名（5.0%）发生自发性早产，335名（3.6%）发生医源性早产，8601名（91.4%）足月分娩。在自发性早产的女性中，妊娠16至22周时，439名中有35名（占8.0%）宫颈长度小于或等于25毫米；妊娠22至30周时，403名中有94名（占23.3%）宫颈长度小于或等于25毫米。妊娠16至22周时，胎儿纤维连接蛋白水平大于或等于50 ng/mL可识别出410名自发性早产女性中的30名（占7.3%），妊娠22至30周时，384名中有31名（占8.1%）。仅在妊娠22至30周时，胎儿纤维连接蛋白水平的受试者操作特征曲线下面积为0.59（95%置信区间，0.56 - 0.62），经阴道宫颈长度单独测量时为0.67（95%置信区间，0.64 - 0.70），两者作为连续变量联合测量时为0.67（95%置信区间，0.64 - 0.70）。
在单胎初产妇中，定量阴道胎儿纤维连接蛋白和连续经阴道超声测量宫颈长度对自发性早产的预测准确性较低。这些发现不支持在此类女性中常规使用这些检测方法。
