Detection of structural abnormalities in the first trimester using ultrasound

Area of Science:

• Obstetrics and Gynecology
• Medical Imaging
• Prenatal Diagnosis

Background:

• Embryonic and early fetal ultrasound diagnosis has become increasingly important in pregnancy care over the last 25 years.
• Modern high-frequency ultrasound transducers provide detailed imaging of the early conceptus and its organs.
• This technological advancement facilitates the relocation of anatomy and anomaly scans from the second to the first trimester.

Purpose of the Study:

• To highlight the evolution and current capabilities of first-trimester ultrasound in detecting embryonic and fetal abnormalities.
• To differentiate between early and late first-trimester diagnostic approaches and their respective methodologies.
• To emphasize the shift towards systematic screening using ultrasound markers in the late first trimester.

Main Methods:

• Utilizing modern high-frequency ultrasound transducers for detailed imaging of the early conceptus.
• Applying transvaginal ultrasound for diagnosis in the early first trimester (up to ~10 weeks).
• Employing transabdominal ultrasound for nuchal translucency screening in the late first trimester.

Main Results:

• Detection of embryonic and fetal structural abnormalities in the first trimester is now frequently reported.
• Early first-trimester abnormalities are often incidentally discovered based on clinical indications.
• Late first-trimester diagnoses are predominantly achieved through systematic screening utilizing specific ultrasound markers.

Conclusions:

• First-trimester ultrasound is a valuable tool for early detection of structural abnormalities.
• Distinguishing between early and late first-trimester diagnosis is crucial, with different methods applied.
• Systematic screening in the late first trimester using ultrasound markers enhances diagnostic accuracy.