What Is an Ultrasound?
Ultrasound allows a health care provider to take pictures of the embryo or fetus as it develops. An ultrasound scan builds a picture of the embryo or fetus on a screen by bouncing sound waves into your uterus. Ultrasound is also called a sonogram. Depending on when it is done during pregnancy, it may
- confirm your due date
- find certain abnormalities
- find multiple pregnancies
- measure the length of your cervix
- show the position and size of the fetus
- show the position of the placenta
Ultrasound is a very safe procedure — no x-rays are involved.
Between 11 and 13 weeks of pregnancy, some providers combine a blood test with a special kind of ultrasound. Some providers refer to this as the combined test. It is used to screen for Down syndrome and other genetic birth defects.
How Is an Ultrasound Done?
There are two ways to do an ultrasound — through the abdomen or through the vagina. Ultrasounds may be performed by your health care provider or by a trained ultrasound technician.
During an abdominal ultrasound, your provider will place the ultrasound wand on your abdomen, using a small amount of gel to help lubricate the area. You may feel pressure during the exam, but it is not painful.
During a vaginal ultrasound, your provider will insert the ultrasound wand into the vagina. This may feel similar to a vaginal exam. You may feel pressure during the exam, but it is not painful.