Elastography in predicting preterm delivery in asymptomatic, low-risk women: a prospective observational study

BMC Pregnancy and Childbirth

Tomasz Paszkowski¹  Ewa Wozniakowska¹  Pawel Milart¹  Piotr Szkodziak¹  Piotr Czuczwar¹  Slawomir Wozniak¹ 

[1] 3rd Chair and Department of Gynecology, Medical University of Lublin, ul. Jaczewskiego 8, Lublin 20-090, Poland

关键词: Cervical assessment;    Ultrasonography;    Preterm delivery;    Elastography;   

Others  :  1125819
DOI  :  10.1186/1471-2393-14-238

 received in 2014-04-11, accepted in 2014-07-14,  发布年份 2014

【 摘 要 】

Background

Despite the efforts to decrease the rate of preterm birth, preterm delivery is still the main cause of neonatal morbidity and mortality. Identifying patients threatened with preterm delivery remains one of the main obstetric challenges. The aim of this study was to estimate the potential value of elastographic evaluation of internal cervical os stiffness at 18-22 weeks of pregnancy in low risk, asymptomatic women in the prediction of spontaneous preterm delivery.

Methods

This prospective observational study included 333 low-risk, asymptomatic women presenting for the routine second trimester ultrasound scan according to the Polish Gynecological Society recommendation between 18-22 weeks of pregnancy. Ultrasound examinations of the cervix were performed transvaginally. The following data were recorded: elastographic color assessment of the internal os and ultrasound cervical length at 18-22 and 30 weeks of pregnancy; maternal age; obstetrical history; presence of cervical funneling at 30 weeks of pregnancy; gestational age at birth. Elastographic assessment of the internal os was performed using a color map: red (soft), yellow (medium soft), blue (medium hard) and purple (hard). If two colors were visible in the region of the internal os, the softer option was noted. Statistical analysis was performed using Statistica software (version 10, Statsoft Poland) using the following tests: chi square test to compare frequency of preterm deliveries in various categories of internal os assessment and Spearman correlation test to determine the correlation between elastographic assessment and cervical shortening. To determine the cut off category of internal os elastography assessment in selecting high preterm delivery risk patients we have calculated the sensivity, specifity, negative predictive value and positive predictive value.

Results

The number of preterm deliveries (<37 weeks of pregnancy) was significantly higher in the red and yellow groups, than in the blue and purple groups. The sensivity, specifity, NPV and PPV for both red and yellow internal os assessment in predicting preterm delivery were 85.7%, 97.6%, 98.3% and 81.1% respectively.

Conclusions

Elastographic assessment of the internal cervical os at 18-22 weeks of pregnancy may identify patients with high risk of preterm delivery in low-risk, asymptomatic women.

【 授权许可】

   
2014 Wozniak et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

Figure 2.

Figure 3.

【 参考文献 】

• [1]Goldenberg RL, Culhane JF, Iams JD, Romero R: Epidemiology and causes of preterm birth. Lancet 2008, 371:75-84.
• [2]Blencowe H, Cousens S, Oestergaard MZ, Chou D, Moller AB, Narwal R, Adler A, Vera Garcia C, Rohde S, Say L, Lawn JE: National, regional and worldwide estimates of preterm birth rates in the year 2010 with time trends since 1990 for selected countries: a systematic analysis and implications. Lancet 2012, 379:2162-2172.
• [3]Rennie JM: Perinatal management at the lower margin of viability. Arch Dis Child 1996, 74:F214-F218.
• [4]Robertson PA, Sniderman SH, Laros RK, Cowan R, Heilbron D, Goldenberg RL, Iams JD, Creasy RK: Neonatal morbidity according to gestational age and birth weight from five tertiary care centers in the United States, 1983 through 1986. Am J Obstet Gynecol 1992, 166:1629-1645.
• [5]Tin W, Wariyar U, Hey E: Changing prognosis for babies of less than 28 weeks’ gestation in the North of England between 1983 and 1994. Br Med J 1997, 314:107-111.
• [6]Aigner F, Mitterberger M, Rehder P, Pallwein L, Junker D, Horninger W, Frauscher F: Status of transrectal ultrasound imaging of the prostate. J Endourol 2010, 24:685-691.
• [7]Kato K, Sugimoto H, Kanazumi N, Nomoto S, Takeda S, Nakao A: Intra-operative application of real-time tissue elastography for the diagnosis of liver tumors. Liver Int 2008, 28:1264-1271.
• [8]Kumm T, Szabunio M: Elastography for the characterization of breast lesions: initial clinical experience. Cancer Control 2010, 17:156-161.
• [9]Rago T, Santini F, Scutari M, Pinchera A, Vitti P: Elastography: new developments in ultrasound for predicting malignancy in thyroid nodules. J Clin Endocrinol Metab 2007, 92:2917-2922.
• [10]Preis K, Swiatkowska-Freund M, Pankrac Z: Elastography in the examination of the uterine cervix before labor induction. Ginekol Pol 2010, 81:757-761.
• [11]Swiatkowska-Freund M, Preis K: Elastography of the uterine cervix: implications for success of induction of labor. Ultrasound Obstet Gynecol 2011, 38:52-56.
• [12]Preis K, Zielinska K, Swiatkowska-Freund M, Wydra D, Kobierski J: The role of elastography in the differential diagnosis of endometrial pathologies–preliminary report. Ginekol Pol 2011, 82:494-497.
• [13]Rechberger T, Uldbjerg N, Oxlund H: Connective tissue changes in the cervix during normal pregnancy and pregnancy complicated by cervical incompetence. Obstet Gynecol 1988, 71:563-567.
• [14]Fuchs T, Woytoń R, Pomorski M, Wiatrowski A, Slejman N, Tomiałowicz M, Florjański J, Milnerowicz-Nabzdyk E, Zimmer M: Sonoelastography of the uterine cervix as a new diagnostic tool of cervical assessment in pregnant women - preliminary report. Ginekol Pol 2013, 84:12-16.
• [15]Myers KM, Socrate S, Paskaleva A, House M: A study of the anisotropy and tension/compression behavior of human cervical tissue. J Biomech Eng 2010, 132:021003.
• [16]Hernandez-Andrade E, Hassan SS, Ahn H, Korzeniewski SJ, Yeo L, Chaiworapongsa TE, Romero R: Evaluation of cervical stiffness during pregnancy using semiquantitative ultrasound elastography. Ultrasound Obstet Gynecol 2013, 41:152-161.
• [17]Khalil MR, Thorsen P, Uldbjerg N: Cervical ultrasound elastography may hold potential to predict risk of preterm birth. Dan Med J 2013, 60:A4570.
• [18]Polish Gynecological Society: Ultrasound section guidelines on ultrasound screening in uncomplicated pregnancy. Ginekol Pol 2012, 83:309-315.
• [19]Iams JD, Goldenberg RL, Meis PJ, Mercer BM, Moawad A, Das A: The length of the cervix and the risk of spontaneous delivery. N Engl J Med 1996, 334:567-572.
• [20]Celik E, To M, Gajewska K, Smith GC, Nicolaides KH: Cervical length and obstetric history predict spontaneous preterm birth: development and validation of a model to provide individualized risk assessment. Ultrasound Obstet Gynecol 2008, 31:549-554.
• [21]Gomez R, Galasso M, Romero R, Mazor M, Sorokin Y, Gonçalves L, Treadwell M: Ultrasonographic examination of the uterine cervix is better than cervical digital examination as a predictor of the likelihood of premature delivery in patients with preterm labor and intact membranes. Am J Obstet Gynecol 1994, 171:956-964.
• [22]Rao A, Celik E, Poggi S, Poon L, Nicolaides KH: Cervical length and maternal factors in expectantly managed prolonged pregnancy: prediction of onset of labor and mode of delivery. Ultrasound Obstet Gynecol 2008, 32:646-651.
• [23]Bauer M, Mazza E, Jabareen M, Sultan L, Bajka M, Lang U, Zimmermann R, Holzapfel GA: Assessment of the in vivo biomechanical properties of the human uterine cervix in pregnancy using the aspiration test: a feasibility study. Eur J Obstet Gynecol Reprod Biol 2009, 144(Suppl 1):S77-S81.
• [24]Cabrol D: Cervical distensibility changes in pregnancy, term and preterm labor. Semin Perinatol 1991, 15:133-139.
• [25]House M, Kaplan DL, Socrate S: Relationships between mechanical properties and extracellular matrix constituents of the cervical stroma during pregnancy. Semin Perinatol 2009, 33:300-307.
• [26]Molina FS, Gómez LF, Florido J, Padilla MC, Nicolaides KH: Quantification of cervical elastography: a reproducibility study. Ultrasound Obstet Gynecol 2012, 39:685-689.
• [27]Fruscalzo A, Schmitz R: Reply. Ultrasound Obstet Gynecol 2013, 41:712-714.
• [28]Londero AP, Bertozzi S, Fruscalzo A, Driul L, Marchesoni D: Ultrasonographic assessment of cervix size and its correlation with female characteristics, pregnancy, BMI, and other anthropometric features. Arch Gynecol Obstet 2011, 283:545-550.
• [29]Fruscalzo A, Schmitz R: Quantitative cervical elastography in pregnancy. Ultrasound Obstet Gynecol 2012, 40:612-613.
• [30]Fruscalzo A, Steinhard J, Londero AP, Fröhlich C, Bijnens B, Klockenbusch W, Schmitz R: Reliability of quantitative elastography of the uterine cervix in at-term pregnancies. J Perinat Med 2013, 41:421-427.
• [31]Yamaguchi S, Kamei Y, Kozuma S, Kawashima H, Komura M, Sugiyama M: Tissue elastography imaging of the uterine cervix during pregnancy. J Med Ultrasonics 2007, 39:209-210.