What Is Ultrasound?

Ultrasound simply uses high frequency sound waves and is believed to be the most accurate and safest method of evaluating the health and gestational age of the fetus. The sound waves are transmitted into the mother and reflected back through a transducer. A computer will then take the signals and convert them to an image that reveals the shape and activity of the fetus.

History And Advancements In Obstetrical Ultrasound

Major advancements of ultrasonography in the last 20 years have allowed us to learn more about the development of the unborn than we knew in 1973. Due to technological advancements of high frequency trans-vaginal sonography, biopsy transducers, and color flow Doppler, we are now able to retrieve vital detailed information which can be used to apply life sustaining treatment before birth.

Routine Use of Ultrasound

Ultrasound is being used effectively in a variety of medical situations. It is commonly applied to detect and verify fetal life, fetal position, multiple pregnancies, placenta location, intrauterine or ectopic pregnancies, anatomic anomalies or bleeding resulting from complete or incomplete abortions. Because of technological advancements made in ultrasound imaging equipment and techniques, "the fetus has reached the patient status," and allows the treating practitioners to meet and exceed what can be determined by routine examination at delivery.

Fetal Biometry

This is a way of measuring the fetus to establish the gestational age.

First Trimester: Crown-Rump measurement (CRL) is the longest dimensional length taken between 6-11 weeks gestation and is accurate to plus or minus three days. If you are unable to visualize the CRL, the gestational sac can be measured.

Second Trimester: Biparietal Diameter (BPD) and the femur length taken from 12 weeks on is accurate to plus or minus ten days. The Head Circumference (HC), Abdominal Circumference and weight may also be measured to compare normal growth patterns.

Safety Of Ultrasound

Diagnostic ultrasound has been used since the late 1950's. Given its known benefits and recognized efficacy for medical diagnosis, including use during human pregnancy, The American Institute of Ultrasound and Medicine (AIUM) has addressed the following statement on the clinical safety and use of diagnostic ultrasound:

Approved March 1988-1994, NO confirmed biological effects on clients or instrument operators caused by exposure at intensities typical of present diagnostic ultrasound instruments have ever been reported. Although the possibility exists that such biological effects may be identified in the future, current data indicate that the benefits to clients of the prudent use of diagnostic ultrasound outweigh the risks, if any, that may be.