Transabdominal Ultrasound in Pregnancy

Recommendations for Ultrasound Evaluation

The American College of Radiology recommends that transabdominal ultrasound becomes the primary method of evaluation as pregnancy advances to the second trimester, being appropriate from approximately 12-14 weeks of gestation 1, 2
The American College of Radiology suggests that transabdominal ultrasound can provide detailed anatomical evaluation from 12-14 weeks onwards 1, 2
A detailed fetal anatomical survey should be performed between 18 and 22 weeks of gestation to evaluate congenital malformations, as recommended by the American College of Radiology 1, 2
From 20 weeks onwards, estimated fetal weight should be calculated and documented in each ultrasound, according to the American College of Radiology 1, 2

A combined transabdominal and transvaginal approach should be performed when possible, allowing for complete evaluation of structures that may be positioned too high for transvaginal visualization alone, as suggested by Praxis Medical Insights 3
The practical sequence recommended is to start with transabdominal to evaluate bladder filling, uterine position, and obtain a general overview of the pelvis, followed by transvaginal for detailed evaluation, according to Praxis Medical Insights 3

Transabdominal ultrasound is the gold standard for detailed anatomical evaluation in the second trimester, between 18-22 weeks, as recommended by the American College of Radiology 1, 2
Transvaginal ultrasound should only be performed if transabdominal evaluation is suboptimal or incomplete, never as the sole approach, according to the American College of Radiology 1, 2