Guidelines for the use of ultrasound in the management of obstetric conditions - September 2007

Section 2: Ultrasound Equipment Standards

Page last updated: September 2007

  1. Transabdominal (TA) transducer
  2. Transvaginal (TV) transducer
  3. B mode imaging
  4. Pulsed Wave (PW) and Colour Doppler (CD)
  5. 3/4 D ultrasound
Colour and pulse wave Doppler are essential for referred scans and recommended for non-referred scans.

Sterilization Techniques for Endocavity Probe

Please refer to the ASUM guidelines in Appendix 3 - Guidelines for Disinfectant of Intracavity Transducers.

Ultrasound Machine

The ultrasound machine should be less than 10 years old.

Ultrasound Transducer

  • Frequency range should be chosen to optimize beam penetration and resolution, and may depend on gestation, indication for scan and patient size.
  • High resolution real-time B-mode scanners with M-mode, colour, power and spectral Doppler.
  • Transabdominal transducers: At least 2 MHz with a range up to 7MHz.
  • Transvaginal probes: At least 5 MHz-preferably 7-9 MHz.
  • 3/4D is not essential but may be useful for certain congenital abnormalities.


It is recommended that images be available for review and stored either as a series of still images digitally or on film, or in real-time on DVD or video. This includes images obtained from both referred and non-referred ultrasound.