Sonography (ultrasound procedure) is a quick, painless diagnostic imaging technique. It uses high-frequency sound waves to produce images of the internal organs. A sonogram is the image that is produced by performing sonography or ultrasonography. During pregnancy, a sonogram is performed to obtain information about how the fetus is developing. It is used to check the fetus's blood flow and heartbeat, as well as estimate its age and delivery date. It is also performed to check the female pelvic organs during pregnancy.
Reasons for Sonography
Sonography is used to monitor and diagnose a wide variety of conditions within nearly any system of the body. A sonogram is often considered a standard part of prenatal care because it can reveal a broad range of information regarding the overall health of both the mother and fetus. Generally, sonograms are conducted in the first trimester of pregnancy, although additional ones may be ordered throughout the second or third trimesters. Additional uses for sonography include the following:
- Determine whether multiple fetuses are present
- Identify problems in the ovaries, placenta or uterus
- Assess the growth, positioning and gender of the fetus
- Identify any physical or developmental problems with the fetus
- Discover the presence of an ectopic pregnancy or miscarriage
- Investigate complications such as infection or bleeding
Sonography is usually part of prenatal care, but for some patients, frequent sonograms are recommended. Women who have previously miscarried, as well as those who experience spotting or complications, may need to undergo additional sonograms as precautionary measures.
The Benefits of Sonography
Sonography is a noninvasive and simple way to procure images of soft tissue, which usually does not show up well on X-rays. It is safe for pregnant women because there is no ionizing radiation involved, and it has no serious side effects. In some cases, however, a sonogram may not detect all birth defects, or may indicate the presence of a birth defect that is not actually there. In most cases, however, a sonogram is considered extremely helpful in detecting abnormalities, and improving a woman's chances for a healthy pregnancy and delivery.
The Sonography Procedure
Most women will have at least two sonograms during a pregnancy. Preparing for sonography varies, depending on the objective of the imaging. A women who is having a sonogram of the uterus or ovaries should have a full bladder; this enables the organs to be more easily viewed.
Sonography begins with the patient's lying down on an examination table, and gel being applied to the skin at the area targeted for imaging. The sonographer moves a special hand-held device (transducer) across the area. The transducer enables sound waves to be transmitted between the body and the device, which then relays information to a computer. Sonograms are typically painless, although some patients may experience slight discomfort. In some cases, sonography may be performed transvaginally. A transvaginal sonogram involves attaching the transducer to a probe that is inserted directly into the vagina.
Whether performed abdominally or transvaginally, a sonogram usually takes about 30 minutes to complete. The images produced by either method are viewed on a computer screen in real time. Results are then analyzed, and findings discussed with the patient.