Routine first-trimester ultrasound screening using a standardized anatomical protocol.

Area of Science:

• Medical Imaging
• Prenatal Diagnosis
• Fetal Medicine

Background:

• First-trimester ultrasound screening for fetal malformations in China has shown variable detection rates.
• Standardized protocols are crucial for improving ultrasound sensitivity in detecting anomalies.
• Previous studies lacked clear specifications for first-trimester standardized sectional views.

Purpose of the Study:

• To evaluate the performance of routine first-trimester ultrasound scans utilizing a standardized anatomic protocol for detecting structural abnormalities in China.

Main Methods:

• A large retrospective study of 59,063 pregnancies was conducted over 7 years.
• Scans were performed between 11 and 13⁺⁶ weeks of gestation.
• A predefined protocol for standardized views was followed for all fetal examinations.

Main Results:

• The overall detection rate for fetal structural abnormalities was 43.1% in 53,349 pregnancies.
• High detection rates were achieved for abdominal wall defects (95.6%) and nervous system defects (66.3%).
• Specific severe anomalies like anencephaly and gastroschisis were robustly detected.

Conclusions:

• Implementing a standardized anatomic protocol is advised for routine first-trimester ultrasound screening.
• Screening for severe structural abnormalities should be extended to the first trimester for early detection.