Infertility Research Today is a free monthly online journal that collates and summarizes the latest research about Infertility, including details on male and female infertility, treatment, causes, pregnancy.

Measurement of the speed of sound in follicular fluid.

Gooding MJ, Barber D, Kennedy SH, Noble JA

Medical Vision Laboratory, Department of Engineering Science, University of Oxford, Parks Road, Oxford OX1 3PJ, UK. gooding@robots.ox.ac.uk

BACKGROUND: Measurement of ovarian follicles by ultrasound is common practice in fertility treatment. However, the effect of the speed of sound is not taken into account. We present results from a study aimed at measuring this. METHODS: The speed of sound was measured in samples of follicular fluid aspirated from patients undergoing fertility treatment. The transmitted and received pulses from a single element ultrasound transducer were recorded using a digital oscilloscope for a pulse passed through a sample of the fluid. The distance over which the pulse travelled was known from calibration with pure water. Variation with temperature was investigated in the range 25-45 degrees C. Dependence on ultrasound frequency, patient and time from aspiration were also investigated. RESULTS: The speed of sound in follicular fluid was found to be 1550+/-3 m/s at 37.3 degrees C using 5.0 MHz ultrasound. The speed varied from 1528+/-3 m/s at 24.8 degrees C to 1561+/-3 m/s at 44.8 degrees C. Variation with patient, time and frequency were not detected. CONCLUSION: The speed of sound in follicular fluid at body temperature is 1550 m/s. This small difference from the speed assumed by the ultrasound machine corresponds to the systematic bias in volume measurement evident in previously published results.

Published 25 January 2005 in Hum Reprod, 20(2): 497-500.
Full-text of this article is available online (may require subscription).

© 2004-2008 Infertility Research Today. All Rights Reserved.