Benefits, Harms, and/or Costs
- 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.
Abbreviations: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)
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This document reflects emerging clinical and scientific advances on the date issued and is subject to change. The information should not be construed as dictating an exclusive course of treatment or procedure to be followed. Local institutions can dictate amendments to these opinions. They should be well-documented if modified at the local level. None of these contents may be reproduced in any form without prior written permission of the publisher.
Women have the right and responsibility to make informed decisions about their care in partnership with their health care providers. To facilitate informed choice women should be provided with information and support that is evidence based, culturally appropriate, and tailored to their needs. The values, beliefs, and individual needs of each woman and her family should be sought, and the final decision about the care and treatment options chosen by the woman should be respected.