Ultrasound: A Picture of Your Baby's Health

From exploring the underwater world of oceans to inspecting the inner world of the human body, sonar technology relies on sound waves to create images of what would otherwise be invisible to us. Your doctor can use sonar technology, too --in a form called ultrasound -- to create a picture of the new life inside your body.

Ultrasound is a common prenatal procedure used even in low-risk pregnancies to confirm your due date or assess your baby's health.

If there are any concerns that your baby may be at risk, ultrasound can help provide the information your doctor needs to give you the best possible prenatal care. Ultrasound is generally agreed to be safe, but feel free to discuss any questions you may have with your doctor.

Most Common Reasons for Ultrasound

• Ultrasound can help your doctor evaluate many conditions related to your pregnancy.  These are some of the most common:

• Unexpected uterus size -- either too large or too small -- may be due to twins or an incorrect estimated age of the baby.

• Vaginal bleeding may indicate conditions such as an ectopic (outside the uterus) pregnancy or a potential miscarriage.

• Previous problems during pregnancy or labor such as major birth defects, premature labor, cesarean section, or stillbirth may reoccur.

• Medical conditions such as high blood pressure or diabetes increase the risk of complications during pregnancy.

During Vaginal Ultrasound

Vaginal ultrasound can be done earlier in pregnancy than abdominal ultrasound -- as early as the fourth week. Because the transducer is closer to your uterus, you and your doctor are able to receive information about your baby's age, location, and heartbeat in spite of the baby's small size. You should have little discomfort during the test, which usually takes less than half an hour to complete.

Doppler Ultrasound

In addition to  vaginal ultrasound, your doctor may use another type of ultrasound. Doppler ultrasound is like an "electronic stethoscope" that allows your doctor to detect your baby's heartbeat early in your pregnancy. Instead of creating images, Doppler ultrasound converts sound waves into an audible signal.  The signal is then amplified for you and your doctor to hear. Doppler ultrasound is becoming part of routine prenatal care, helping your doctor detect and monitor your baby's heartbeat.\

What Ultrasound Shows

In early pregnancy, ultrasound shows:

• The location of your pregnancy -- inside or outside (ectopic) --  your uterus

• Your baby's heartbeat, movement, or other signs of life

• The size of your baby to establish an accurate due date

• The number of babies you are carrying