What is the typical frequency range used in obstetric sonography?

The typical frequency range used in obstetric sonography is indeed best represented by a range of 3 to 5 MHz. This frequency range strikes a balance between resolution and penetration, which is essential in imaging the developing fetus during pregnancy. Frequencies in this range allow for adequate detail to assess fetal structures while ensuring sufficient depth of penetration to visualize the fetus comfortably within the uterus.

In obstetric applications, higher frequencies provide better resolution but have limited penetration and may not effectively visualize deeper structures, especially in cases of obesity or when the fetus is positioned deeply within the pelvis. Conversely, lower frequencies offer greater penetration but produce images with lower resolution, which can obscure important anatomical details required for accurate assessments.

Understanding the appropriate frequency for obstetric sonography is crucial for obtaining clear and diagnostic images, which aids in monitoring fetal development and detecting any anomalies. The range of 3 to 5 MHz is widely accepted and used in the field, making it the correct choice for this question.