Published online by Cambridge University Press: 01 February 2010
Introduction
Ultrasound (US) is an essential part of infertility evaluation of the female, and is indispensable for obtaining optimal results from intrauterine insemination (IUI) and ovulation induction (OI). Use of US for evaluation and management of infertility is of recent origin. The first report of follicle changes throughout a complete menstrual cycle appeared in 1979. Sonohysterography (SHG), instillation of sonolucent fluid into the uterus in order to improve visualization of the fallopian tubes and soft tissue abnormalities of the uterine cavity, followed in 1984. Recent developments include the use of three-dimensional US to delineate uterine structural abnormalities, and the adoption of color Doppler blood-flow analysis of uterine and ovarian blood vessels.
Transabdominal ultrasound (AUS) is the preferred method for evaluation of pelvic masses larger than 5 cm, and for evaluation of the pregnant uterus after the first trimester. Transabdominal US requires a distended bladder, which is uncomfortable for the patient, particularly when pressure is applied on the lower abdomen during scanning. Accurate delineation of pelvic structures is not possible in all women due to beam scatter by excessive subcutaneous fat and overlying gas-filled bowel loops, or when the ovaries and uterus are located deep in the pelvis. Transabdominal US utilizes frequencies between 2.5 and 3.5 MHz. As frequency is increased, imaging depth decreases and ambiguity occurs because of attenuation. For soft tissue, attenuation in decibels (dB) is approximately 0.5 dB per cm for each MHz of frequency.
To save this book to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.