Detection of fetal structural anomalies in a basic first-trimester screening program for aneuploidy

Area of Science:

• Medical Imaging
• Prenatal Diagnosis
• Genetics

Background:

• First-trimester aneuploidy screening sonography is a key component of prenatal care.
• Credentialed sonographers play a vital role in accurate fetal anomaly detection.
• Early identification of fetal anomalies impacts management and outcomes.

Purpose of the Study:

• To evaluate the utility of first-trimester aneuploidy screening sonography for detecting fetal anomalies.
• To assess the detection rate of fetal anomalies between 11 and 14 weeks' gestation by credentialed sonographers.

Main Methods:

• Retrospective cohort study of 9692 fetuses undergoing nuchal translucency (NT) scans.
• Data collected from January 2008 to June 2012 at a private ultrasound facility.
• Anomalies categorized as lethal, major, or minor; detection rates compared between NT scan and later anatomic survey.

Main Results:

• 1.8% of fetuses had anomalies detected (50 at NT scan, 130 at anatomic scan).
• Credentialed sonographers detected 41.4% of major or lethal anomalies during the NT scan.
• Two suspected abnormalities at NT scan were not confirmed later.

Conclusions:

• First-trimester aneuploidy screening sonography by credentialed sonographers is valuable for detecting significant fetal anomalies.
• This early screening identifies a substantial proportion of major and lethal anomalies.
• The findings support the role of early sonography in prenatal anomaly detection.