Am J Perinatol 2016; 33(10): 957-965
DOI: 10.1055/s-0036-1579652
Original Article
Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

The Performance of First-Trimester Anatomy Scan: A Decision Analysis

Lorie M. Harper
1  Department of Obstetrics and Gynecology, The University of Alabama at Birmingham, Center for Women's Reproductive Health, Birmingham, Alabama
,
S. Lindsay Wood
1  Department of Obstetrics and Gynecology, The University of Alabama at Birmingham, Center for Women's Reproductive Health, Birmingham, Alabama
,
Sheri M. Jenkins
1  Department of Obstetrics and Gynecology, The University of Alabama at Birmingham, Center for Women's Reproductive Health, Birmingham, Alabama
,
John Owen
1  Department of Obstetrics and Gynecology, The University of Alabama at Birmingham, Center for Women's Reproductive Health, Birmingham, Alabama
,
Joseph R. Biggio
1  Department of Obstetrics and Gynecology, The University of Alabama at Birmingham, Center for Women's Reproductive Health, Birmingham, Alabama
› Author Affiliations
Further Information

Publication History

18 December 2015

18 January 2016

Publication Date:
22 April 2016 (online)

Abstract

Introduction First-trimester ultrasound (US) for anatomy assessment may improve anomaly detection, but it may also increase overall US utilization. We sought to assess the utility of first-trimester US for evaluation of fetal anatomy.

Materials and Methods A decision analytic model was created to compare first- plus second-trimester anatomy scans to second-trimester scan alone in four populations: general, normal weight women, obese women, and diabetics. Probability estimates were obtained from the literature. Outcomes considered were number of: major structural anomalies detected, US performed, and false-positive US. Multivariable sensitivity analyses were performed to evaluate the consistency of the model with varying assumptions.

Results A strategy of first- plus second-trimester US detected the highest number of anomalies but required more US examinations per anomaly detected. The addition of a first-trimester anatomy US was associated with a small increase in the false-positive US (< 10/10,000). In populations with higher anomaly prevalence and lower second-trimester US sensitivity (i.e., diabetes, obesity), the number of additional US performed per anomaly detected with the first-trimester US was < 60.

Discussion In high-risk populations, a first-trimester US in addition to a second-trimester US may be a beneficial approach to detecting anomalies.

Abstract presented as a poster at 35th Annual Meeting of the Society for Maternal-Fetal Medicine, The Pregnancy Meeting; February 2–7, 2015; San Diego, CA.