Comparative Study of Learning Curve for First Trimester Fetal Anomaly Scan

A Comparative Study of Learning Curve Between Two Different Levels of Proficiency for First Trimester Fetal Anomaly Scan Using ISUOG Guidelines

Ultrasound scans during first trimester are more difficult than routine mid-trimester ultrasound scans. Practice guidelines for first trimester fetal ultrasound scans have been provided by the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) since 2013. Using this guidelines, different levels of proficiency operators might have equal ability to complete first trimester ultrasound scans.

Nowadays, high-resolution transabdominal ultrasounds are widely used, and ultrasound scans for fetal structural abnormalities at the first trimester are indeed possible. First trimester ultrasound scans are important and essential for detecting fetal structural anomalies, and they help provide optimized early antenatal management. However, ultrasound scans, during this period, are more difficult than routine mid-trimester ultrasound scans, as fetal organs are small and experienced operators are needed to use the transducer to obtain informative pictures. Practice guidelines for first trimester fetal ultrasound scans have been provided by the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) since 2013. Since then, the percentage of complete scans and the high detection rate of fetal structural abnormalities during first trimester ultrasound scans have been reported. From our perspective, ultrasound operators who have different experiences in mid-trimester ultrasound scanning might have equal ability to complete first trimester ultrasound scans using the ISUOG guidelines. The objective of this study is to compare the rate of completed scans regarding fetal structures at the first trimester ultrasound scan between two different levels of proficiency operators.

After recruitment, the participants were divided into two groups to perform first-trimester ultrasound scan by two different levels of proficiency. First group : operator has experience more than 3 years in NT scan and second trimester ultrasound scan Second group : operator has experience less than 3 years in NT scan and second trimester ultrasound scan

Percent of completed scans of fetal structural abnormality between two different levels of proficiency operators

To compare the percentage of completed scans of each organ during the first trimester scan between two different levels of proficiency

Screening time for first trimester ultrasound scans between two different levels of proficiency operators

To compare screening time for first trimester ultrasound scans between two different levels of proficiency operators

Learning curve of first trimester ultrasound scans between two different levels of proficiency operators

Detection rate of fetal structural abnormality in first trimester ultrasound scans between two different levels of proficiency operators

To compare the detection rate of fetal structural abnormality between two different levels of proficiency operators

Inclusion Criteria: Singleton pregnancy Maternal age ≥ 18 years Gestational age between 11-13 + 6 weeks by last menstrual date or ultrasound report if uncertain date Exclusion Criteria: Multifetal gestation Miscarriage before first trimester ultrasound Loss to follow up at mid-trimester ultrasound scan Loss to follow up after birth

Department of Obstetrics and Gynecology, Faculty of Medicine Ramathibodi hospital, Mahidol university

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