Our Services

Obstetrical Ultrasound

What is Ultrasound?

Diagnostic ultrasound is the use of high frequency sound waves to visualize structures within the body. A small device called a transducer is used to send sound waves into the body, which are then reflected off of internal structures. The returning sound waves (echoes) are then sent back to the same transducer, and the ultrasound machine electronically changes the echoes into a picture (image) of your internal structures and your fetus.

Is Ultrasound Safe?

Diagnostic ultrasound has been in use for over 25 years. The American Institute of Ultrasound in Medicine has issued the following statement in regards to the clinical safety of ultrasound: "No confirmed biological effects on patients or instrument operator caused by exposure at intensities typical of present diagnostic 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 patients of the prudent use of diagnostic ultrasound outweigh the risks, if any, that may be present." The physicians at SFPA will assure that ultrasound will be used prudently and safely throughout your pregnancy.

Is special training needed to perform an ultrasound examination?

Yes, all of our physicians have special training in performing obstetric ultrasound examinations and have extensive experience in managing pregnancies where ultrasound abnormalities are found. In addition, all of our ultrasound technicians are registered diagnostic medical sonographers. Our center has been certified by the American Institute of Ultrasound in Medicine (AIUM).

Will Ultrasound Hurt?

The procedure itself is painless, but in order to obtain the best image possible, mild discomfort might occur from some pressure or angling in an unusual direction. Warm ultrasound gel is applied to the skin surface so that the transducer will have better contact. For some ob exams, it may be necessary to place the transducer inside the vagina, however most women do not find this uncomfortable.

What are the reasons for a first trimester ultrasound (6-12 weeks gestation)?

A first trimester ultrasound can be performed for several reasons. The most common are to confirm the gestational age of your pregnancy and to measure the fetal neck as part of a screening program for Down syndrome. Other common reasons include vaginal bleeding or history of a cervical problem. As part of the ultrasound examination, the fetus will be measured to verify or determine your due date. An endovaginal ultrasound may be needed to help visualize the fetus or cervix at this stage of pregnancy.

What is a fetal survey?

A fetal survey is a detailed ultrasound examination performed at 18-20 weeks of gestation to assess the growth and development of your fetus. The survey typically includes evaluation of both internal and external fetal structures. The placenta and uterus will also be assessed. Ultrasound, which is the best screening test available, detects approximately 70% of major structural abnormalities in the fetus (this means that 30% of abnormalities may be missed). During this examination it may be possible to note the sex of the fetus.

What is 3D ultrasound?

A 3D ultrasound is an ultrasound performed with a special machine utilizing a high speed computer that produces a three dimensional like image of the fetus. All of the ultrasound machines at SFPA are GE Volusons capable of producing 3D images. If the fetus is in a favorable position, we will try to provide a 3D image to you.

How long will the ultrasound examination take?

Most ultrasound examinations take 30 to 45 minutes. You will first be seen by one of our ultrasound technicians. A physician will then go over the images that have been obtained and will frequently perform a short confirmatory examination.

What if my ultrasound is not normal?

Fetal abnormalities may be detected as early as 6-12 weeks gestation, even though the fetus is small at this stage of pregnancy. During the fetal survey (18-20 weeks), structural abnormalities or findings that may be associated with an increased risk of a chromosomal abnormality may be detected. The use of 3D ultrasound at a high risk center, such as SFPA, can provide additional diagnostic information about many types of fetal abnormalities. If an abnormality is suspected at any gestational age, the findings will be discussed with you and your obstetrician by a physician at SFPA. Additionally, you may be referred to another specialist for further evaluation.

How many ultrasounds will I have in my pregnancy?

Most women will have a first trimester ultrasound and a fetal survey. A later ultrasound may be performed to check the fetal size or as a follow-up to something that was noted at the time of fetal survey.

What preparation is needed before my ultrasound?

For a first trimester ultrasound examination please drink 16 ounces of liquid 30 minutes before your appointment and arrive with a full bladder. There is no special preparation for a fetal survey or ultrasound performed later in gestation.