No. 352-Technical Update: The Role of Early Comprehensive Fetal Anatomy Ultrasound Examination



      This guideline presents an evidence-based technical update and recommendations for the performance of early comprehensive fetal anatomic scanning (ECFAS) at 11 to 16 weeks' gestation.


      Patients at high risk for fetal anomalies and in whom traditional mid–second trimester transabdominal imaging may be challenging or who may benefit from earlier identification of fetal anomalies may be suitable for early fetal anatomy scanning.


      This practice may result in earlier identification of fetal anomalies and provide earlier intervention options in high-risk populations and/or in populations where mid–second trimester transabdominal scanning is challenging.

      Target Population

      This population consists of obstetrical patients in whom mid–second trimester ultrasound scanning will be technically challenging and patients who are at higher risk for major fetal anomalies.


      Published literature was retrieved through searches of PubMed and Medline in 2016 using key words. Results were restricted to controlled clinical trials, reviews, and observational studies published in English. There were no date restrictions, and searches were updated in the guideline to 2016. Grey (unpublished) literature was identified through searching the websites of health technology assessment and clinical practice guidelines and national and international medical specialty societies. No relevant studies were found.

      Validation Methods

      The content and recommendations were drafted and agreed on by the principal authors. The Board of the SOGC approved the final draft for publication. The quality of evidence was rated using the criteria described in the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology framework.

      Benefits, Harms, and/or Costs

      It is anticipated that there will be an increase in earlier detection of major fetal anomalies in the target population with the benefits of earlier interventions for those individuals. In areas where the service is not available the patient may need to travel to a nearby centre. Early fetal anatomy scanning is considered to be safe and is not expected to cause a risk to the pregnancy.

      Guideline Update

      Evidence will be reviewed 5 years after publication to decide whether all or part of the guideline should be updated. However, if important new evidence is published before the 5-year cycle, the review process may be accelerated for a more rapid update of some recommendations.


      This technical update was developed with resources funded by the SOGC.

      Summary Statements

      • 1.
        Development of fetal organs begins early in the first trimester, with the majority of organs visible by ultrasound evaluation towards the end of the first trimester of pregnancy (High).
      • 2.
        The majority of significant and sonographically detectable fetal anomalies can be detected on early fetal anatomic ultrasound assessment (High).
      • 3.
        Early detection of fetal anomalies allows patients to obtain counselling consultations, and genetic testing at an earlier gestational age, as well as more time to consider options for pregnancy management (High).


      • 1.
        Medical personnel (physicians, technologists, or ultrasound practitioners) who have substantial experience or training in the assessment and interpretation of early comprehensive fetal anatomic scanning should be performing the examination (Strong, High).
      • 2.
        The examination can be performed transvaginally, transabdominally, or by both approaches, and the choice for each mode depends on the fetal position, the gestational age, and the experience of the operator (Strong, High).
      • 3.
        Early comprehensive fetal anatomic scanning at 13–16 weeks' gestation should be considered for women who have higher risk for significant fetal anomalies or in whom it is anticipated that a midtrimester transabdominal scan will be technically challenging (High). This scan does not replace the routine 18- to 22-week anatomy scan.

      Key Words


      ECFAS (early comprehensive fetal anatomic scanning), GA (gestational age), IT (intracranial translucency), NB (nasal bone), NT (nuchal translucency), SOGC (Society of Obstetricians and Gynaecologists of Canada)
      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Journal of Obstetrics and Gynaecology Canada
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Cargill Y.
        • Morin L.
        • Bly S.
        • et al.
        Content of a complete routine second trimester obstetrical ultrasound examination and report.
        J Obstet Gynaecol Can. 2009; 31 (6-80): 272-275
        • Comas G.C.
        • Galindo A.
        • Martinez J.M.
        • et al.
        Early prenatal diagnosis of major cardiac anomalies in a high-risk population.
        Prenat Diagn. 2002; 22: 586-593
        • Bronshtein M.
        • Zimmer E.Z.
        • Milo S.
        • et al.
        Fetal cardiac abnormalities detected by transvaginal sonography at 12–16 weeks' gestation.
        Obstet Gynecol. 1991; 78: 374-378
        • Salomon L.J.
        • Alfirevic Z.
        • Bilardo C.M.
        • et al.
        ISUOG practice guidelines: performance of first-trimester fetal ultrasound scan.
        Ultrasound Obstet Gynecol. 2013; 41: 102-113
      1. Grading of Recommendations, Assessment, Development and Evaluation (GRADE) Working Group Schünemann H. Brożek J. The GRADE handbook. GRADE Working Group, 2013 (Available at)
        • Iliescu D.
        • Tudorache S.
        • Comanescu A.
        • et al.
        Improved detection rate of structural abnormalities in the first trimester using an extended examination protocol.
        Ultrasound Obstet Gynecol. 2013; 42: 300-309
        • Grande M.
        • Arigita M.
        • Borobio V.
        • et al.
        First-trimester detection of structural abnormalities and the role of aneuploidy markers.
        Ultrasound Obstet Gynecol. 2012; 39: 157-163
        • Novotna M.
        • Haslik L.
        • Svabik K.
        • et al.
        Early anatomy ultrasound in women at increased risk of fetal anomalies.
        Ceska Gynekol. 2012; 77: 330-335
        • Pilalis A.
        • Basagiannis C.
        • Eleftheriades M.
        • et al.
        Evaluation of a two-step ultrasound examination protocol for the detection of major fetal structural defects.
        J Matern Fetal Neonatal Med. 2012; 25: 1814-1817
        • Abu-Rustum R.S.
        • Daou L.
        • Abu-Rustum S.E.
        Role of first-trimester sonography in the diagnosis of aneuploidy and structural fetal anomalies.
        J Ultrasound Med. 2010; 29: 1445-1452
        • Ebrashy A.
        • El Kateb A.
        • Momtaz M.
        • et al.
        13-14-week fetal anatomy scan: a 5-year prospective study.
        Ultrasound Obstet Gynecol. 2010; 35: 292-296
        • Oztekin O.
        • Oztekin D.
        • Tinar S.
        • Adibelli Z.
        Ultrasonographic diagnosis of fetal structural abnormalities in prenatal screening at 11–14 weeks.
        Diagn Interv Radiol. 2009; 15: 221-225
        • Dane B.
        • Dane C.
        • Sivri D.
        • et al.
        Ultrasound screening for fetal major abnormalities at 11–14 weeks.
        Acta Obstet Gynecol Scand. 2007; 86: 666-670
        • Becker R.
        • Wegner R.D.
        Detailed screening for fetal anomalies and cardiac defects at the 11-13-week scan.
        Ultrasound Obstet Gynecol. 2006; 27: 613-618
        • Saltvedt S.
        • Almström H.
        • Kublickas M.
        • et al.
        Detection of malformations in chromosomally normal fetuses by routine ultrasound at 12 or 18 weeks of gestation: a randomised controlled trial in 39 572 pregnancies.
        BJOG. 2006; 113: 664-674
        • Srisupundit K.
        • Tongsong T.
        • Sirichotiyakul S.
        • et al.
        Fetal structural anomaly screening at 11–14 weeks of gestation at Maharaj Nakorn Chiang Mai Hospital.
        J Med Assoc Thai. 2006; 89: 588-593
        • Souka A.P.
        • Pilalis A.
        • Kavalakis I.
        • et al.
        Screening for major structural abnormalities at the 11- to 14-week ultrasound scan.
        Am J Obstet Gynecol. 2006; 194: 393-396
        • Chen M.
        • Lam Y.H.
        • Lee C.P.
        • et al.
        Ultrasound screening of fetal structural abnormalities at 12 to 14 weeks in Hong Kong.
        Prenat Diagn. 2004; 24: 92-97
        • Munim S.
        • Khowaja N.
        Effectiveness of early pregnancy ultrasound in diagnosing fetal abnormalities in high risk women.
        J Pak Med Assoc. 2004; 54: 542-544
        • Taipale P.
        • Ammala M.
        • Salonen R.
        • et al.
        Two-stage ultrasonography in screening for fetal anomalies at 13–14 and 18–22 weeks of gestation.
        Acta Obstet Gynecol Scand. 2004; 83: 1141-1146
        • Carvalho M.H.
        • Brizot M.L.
        • Lopes L.M.
        • et al.
        Detection of fetal structural abnormalities at the 11–14 week ultrasound scan.
        Prenat Diagn. 2002; 22: 1-4
        • Economides D.L.
        • Braithwaite J.M.
        First trimester ultrasonographic diagnosis of fetal structural abnormalities in a low risk population.
        Br J Obstet Gynaecol. 1998; 105: 53-57
        • Whitlow B.J.
        • Economides D.L.
        First trimester detection of fetal abnormalities in an unselected population.
        Contemp Rev Obstet Gynaecol. 1998; 10: 245-253
        • Blaas H.G.
        Detection of structural abnormalities in the first trimester using ultrasound.
        Best Pract Res Clin Obstet Gynaecol. 2014; 28: 341-353
        • Farraposo S.
        • Montenegro N.
        • Matias A.
        Evaluation of the role of first-trimester obstetric ultrasound in the detection of major anomalies: a systematic review.
        J Perinat Med. 2014; 42: 141-149
        • Rossi A.C.
        • Prefumo F.
        Accuracy of ultrasonography at 11–14 weeks of gestation for detection of fetal structural anomalies: a systematic review.
        Obstet Gynecol. 2013; 122: 1160-1167
        • Sinkovskaya E.
        • Fleenor J.
        • Klassen A.
        • et al.
        Fetal cardiac imaging in early pregnancy: analysis of 254 echocardiograms performed between 11+0 and 16+6 weeks gestation.
        J Am Soc Echocardiogr. 2013; 26: B4
        • Eleftheriades M.
        • Tsapakis E.
        • Sotiriadis A.
        • et al.
        Detection of congenital heart defects throughout pregnancy: impact of first trimester ultrasound screening for cardiac abnormalities.
        J Matern Fetal Neonatal Med. 2012; 25: 2546-2550
        • Rasiah S.V.
        • Publicover M.
        • Ewer A.K.
        • et al.
        A systematic review of the accuracy of first-trimester ultrasound examination for detecting major congenital heart disease.
        Ultrasound Obstet Gynecol. 2006; 28: 110-116
        • Westin M.
        • Saltvedt S.
        • Bergman G.
        • et al.
        Routine ultrasound examination at 12 or 18 gestational weeks for prenatal detection of major congenital heart malformations? A randomised controlled trial comprising 36 299 fetuses.
        BJOG. 2006; 113: 675-682
        • Gabriel C.C.
        • Rodriguez P.P.
        Echocardiography in early pregnancy.
        Donald School J Ultrasound Obstet Gynecol. 2013; 7: 168-181
        • Haak M.C.
        • Bartelings M.M.
        • Gittenberger-De Groot A.C.
        • et al.
        Cardiac malformations in first-trimester fetuses with increased nuchal translucency: ultrasound diagnosis and postmortem morphology.
        Ultrasound Obstet Gynecol. 2002; 20: 14-21
        • Carvalho J.S.
        • Moscoso G.
        • Ville Y.
        First-trimester transabdominal fetal echocardiography.
        Lancet. 1998; 351: 1023-1027
        • Bronshtein M.
        • Zimmer E.Z.
        • Gerlis L.M.
        • et al.
        Early ultrasound diagnosis of fetal congenital heart defects in high-risk and low-risk pregnancies.
        Obstet Gynecol. 1993; 82: 225-229
        • Souka A.P.
        • Pilalis A.
        • Kavalakis Y.
        • et al.
        Assessment of fetal anatomy at the 11-14-week ultrasound examination.
        Ultrasound Obstet Gynecol. 2004; 24: 730-734
        • Taipale P.
        • Ammala M.
        • Salonen R.
        • et al.
        Learning curve in ultrasonographic screening for selected fetal structural anomalies in early pregnancy.
        Obstet Gynecol. 2003; 101: 273-278
        • Rosati P.
        • Guariglia L.
        Prognostic value of ultrasound findings of fetal cystic hygroma detected in early pregnancy by transvaginal sonography.
        Ultrasound Obstet Gynecol. 2000; 16: 245-250
        • Bly S.
        • Van den Hof M.C.
        • Diagnostic Imaging Committee SoO, Gynaecologists of C
        Obstetric ultrasound biological effects and safety.
        J Obstet Gynaecol Can. 2005; 27: 572-580
        • Levmore-Tamir M.
        • Tsafrir A.
        • Boldes R.
        • et al.
        Early second trimester transvaginal ultrasound anomaly scan does not cause adverse perinatal outcome.
        Early Hum Dev. 2015; 91: 239-242
        • Whitworth M.
        • Bricker L.
        • Neilson J.P.
        • et al.
        Ultrasound for fetal assessment in early pregnancy.
        Cochrane Database Syst Rev. 2010; (CD007058)
        • Salvesen K.
        • Lees C.
        • Abramowicz J.
        • et al.
        ISUOG statement on the safe use of Doppler in the 11 to 13 +6-week fetal ultrasound examination.
        Ultrasound Obstet Gynecol. 2011; 37: 628