Frequency and Importance of Incomplete Screening Fetal Anatomic Sonography in Pregnancy.
OBJECTIVE
To determine (1) how often routine screening fetal anatomic sonography fails to completely visualize fetal anatomy; (2) the proportion of women with incomplete ultrasound examinations who are recommended for repeat screening and then undergo repeat sonography; and (3) how often abnormal fetal anatomy is detected on repeat sonography.


METHODS
We conducted a retrospective cohort study at a high-volume academic obstetric ultrasound center. Participants were 16,300 women at 17 through 21 weeks' gestation with a singleton pregnancy presenting for screening anatomic sonography between January 2009 and December 2013. Main outcome measures were (1) incomplete visualization of anatomy at initial screening sonography; (2) among women with incomplete but otherwise normal initial screening ultrasound examinations, recommendation for and performance of repeat sonography; and (3) among women undergoing repeat sonography, discovery of abnormal fetal anatomy within anatomic components that were previously incompletely visualized.


RESULTS
The mean maternal age ± SD was 30.8 ± 6.3 years, and the mean gestational age was 18.8 ± 1.0 weeks. Among 16,300 initial screening ultrasound examinations, 2157 (13.2%) had incomplete visualization of fetal anatomy. Of those women eligible for follow-up, 91.5% were recommended for repeat screening, of whom 92.8% had a subsequent examination. Of 1560 repeat screening ultrasound examinations, 8 (0.5%) showed an abnormality in the components of anatomy that were previously visualized incompletely.


CONCLUSIONS
In this large single-center study, incomplete visualization was common in screening fetal anatomic ultrasound examinations. Recommendations for repeat imaging were nearly universal, but abnormal fetal anatomy was infrequently discovered on repeat screening.
Robert Wood Johnson Foundation Clinical Scholars Program, New Haven, Connecticut USA mark.silvestri@yale.edu.|Department of Obstetrics, Gynecology, and Reproductive Sciences, New Haven, Connecticut USA mark.silvestri@yale.edu.
Mark T
MT
Silvestri
Department of Obstetrics, Gynecology, and Reproductive Sciences, New Haven, Connecticut USA.
Christian M
CM
Pettker
Yale School of Medicine, New Haven, Connecticut USA.
Julia H
JH
Raney
Department of Obstetrics, Gynecology, and Reproductive Sciences, New Haven, Connecticut USA.
Xiao
X
Xu
Robert Wood Johnson Foundation Clinical Scholars Program, New Haven, Connecticut USA.|Department of Internal Medicine, New Haven, Connecticut USA.
Joseph S
JS
Ross
D000328:Adult; D015331:Cohort Studies; D000013:Congenital Abnormalities / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D011247:Pregnancy; D015203:Reproducibility of Results; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal / Q000379:methods* / Q000706:statistics & numerical data*
fetal anatomy; obstetric ultrasound; prenatal screening; prenatal sonography