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

Abstract

Tweetable AbstractMost detectable fetal anomalies are present in early pregnancy. Early fetal anatomy at 13-16 weeks, performed by trained operator, should be considered for women at high risk for fetal anomalies or when the routine mid-trimester anatomy scan may be technically challenging. SUMMARY STATEMENTS1.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). RECOMMENDATIONS1.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 (strong, high). This scan does not replace the routine 18- to 22-week anatomy scan.