If you're like most women, you'll have a routine ultrasound about now so your caregiver can get information on your baby's health. Though this brief (5 to 10 minutes) and painless test is most often done during the second trimester, it can be performed any time between the fifth week of gestation and delivery.
There are two types of ultrasounds: transvaginal and transabdominal. With both, you lie on your back on an exam table while your belly or a probe is lubed with a special gel. A transducer (a small microphone-like device) is gently pressed on your belly or inserted into your vagina. The method used depends on how far along you are and what type of equipment is on hand. The transabdominal transducer is moved over your belly. It works by sending out high-frequency sound waves and then picking up the sound waves that bounce back off the bones and tissues in the body. These sound waves then produce an image on a nearby computer screen. The image on the screen, which for some is crystal clear and for others a big blur, is your baby. Regardless, most expectant moms find this first glimpse thrilling -- and over all too quickly.
Ultrasound is a non-invasive test that provides a tremendous amount of information to your health care provider about your baby's development and health. Some of the things that can be seen by ultrasound include:
- Determine an accurate gestational age of the baby
- Determine sex of the baby
- See any anatomical abnormalities that exist in the baby
- Determine if it is just one baby or more than one
- See the location of the placenta and the baby's position within the uterus
- See the amount of amniotic fluid
- Watch how the baby's heart is beating