What is a fetal ultrasound?
Fetal ultrasound is a test that lets your doctor see an image of your baby. Your doctor learns information about your baby from this picture. You may find out, for example, if you are having a boy or a girl. But the main reason you have this test is to get information about your baby's health.
(You may hear your baby called a fetus. This is a common medical term for a baby that's growing in the mother's uterus.)
Why is a second-trimester fetal ultrasound done?
In the second trimester, a fetal ultrasound is done to:
- Estimate the number of weeks and days a fetus has developed since the beginning of the pregnancy. This is called the gestational age.
- Look at the size and position of the fetus, the placenta, and the fluid that surrounds the fetus.
- Find major birth defects, such as heart problems or problems with the brain and spinal cord (neural tube defects). But the test may not be able to find many minor defects and some major birth defects.
How is a second-trimester fetal ultrasound done?
- You may be able to leave your clothes on, or you will be given a gown to wear.
- You will lie on your back on a padded examination table.
- A gel will be spread on your belly. It will be removed after the test.
- A small, handheld device called a transducer will be pressed against the gel on your skin and moved across your belly several times.
- You may watch the monitor to see the picture of your baby during the test.
How do you prepare for a fetal ultrasound?
In general, there's nothing you have to do before this test, unless your doctor tells you to.
What does an abnormal fetal ultrasound result mean?
Abnormal seems to imply that something is wrong with your baby. But what it means is that the test has shown something the doctor wants to take a closer look at.
And that's what happens next. Your doctor will talk to you about what further test or tests you may need.
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