Maternal and Fetal Testing Overview
Most women have healthy pregnancies and their babies are born without difficulties. However, women with high-risk pregnancies often need to be closely watched for potential problems or complications. Fortunately, there are many tests and procedures to monitor the health of both mother and baby. Many of these pose little or no risk and can provide tremendous amounts of information to doctors, midwives, and expectant parents. Some types of testing and procedures, however, do carry some risks to mother, baby, or both. For this reason, if you are offered prenatal testing, it is important to discuss with your doctor or midwife the following questions:
Why is the test needed for your pregnancy?
What information will the test give?
What are the benefits of the test?
What are the risks, if any, to you and to your baby?
What other tests might be used instead?
Who will do the test?
Where will it be done?
How long does it take to get results?
Will the test results require additional testing?
What are your options based on the outcome of the test?
What are your options if you choose to not have the test?
Some mothers are more likely to need a closer watch on their pregnancy. Some conditions that may warrant maternal and fetal testing include the following:
Pre-existing maternal diseases (for example, diabetes, high blood pressure, kidney disease, heart disease)
Abnormal amniotic fluid amounts
Abnormal fetal growth
Multiple pregnancy (twins or more)
Very young or older than 35 years old
What is fetal monitoring?
In pregnancy and during labor, your doctor will want to check the health of your unborn baby (fetus). This is done by check the baby’s heart rate and other functions. Monitoring can be done on the outside of your belly (external monitoring). Or it may be done directly on the baby while inside the womb (internal monitoring). Fetal monitoring is a very common procedure.
External monitoring may done with a special tool called a fetoscope. It’s a stethoscope that has a different shape. It may also be done using Doppler. This is an electronic tool that uses sound waves and a computer. Internal monitoring is done by putting a small sticky pad (electrode) on the baby’s head. This is done while it’s still in the mother’s womb.
Fetal heart rate monitoring is used to check the rate and rhythm of the heartbeats. It looks for any increases or decreases in the baby’s heartbeat. It also checks how much the baby’s heart rate changes. The average fetal heart rate is between 110 and 160 beats per minute. The fetal heart rate may change as the baby responds to conditions in the uterus. An abnormal fetal heart rate or pattern may mean that the baby is not getting enough oxygen or there are other problems. An abnormal pattern also may mean that an emergency cesarean (c-section) delivery is needed.
Why might I need fetal monitoring?
Using a handheld Doppler device to listen to the fetal heartbeat is the most basic type of fetal monitoring. This is often done during prenatal visits to count the fetal heart rate.
Fetal monitoring may also help show problems in the baby during late pregnancy and labor. It can show if other testing or a c-section may be needed.
What are the risks of fetal monitoring?
There are no known physical risks for external monitoring with a fetoscope or Doppler. There may be a slight risk of infection with internal monitoring. The scalp electrode may also cause a mark or small cut on the baby's head, but this often heals quickly.
An abnormal fetal heart rate pattern doesn’t always mean the baby is in danger. But electronic fetal monitoring is linked with a greater chance for vacuum and forceps use, and for c-section delivery. Talk with your healthcare provider about these risks.
How do I get ready for fetal monitoring?
Preparing for fetal monitoring depends on if it is external or internal and if it is being done late in pregnancy or during labor.
For external fetal monitoring during pregnancy with a Doppler, you may need to have a full bladder. There is no restriction of food or drink. You’ll be given a consent form to sign. Make sure to ask questions if needed.
For fetal monitoring during labor, your healthcare provider will tell you if any preparation is needed.
What happens during fetal monitoring?
The details may vary, but typical electronic fetal monitoring may go like this:
- The provider will put gel on your belly. This helps to send sound waves from your belly to the computer.
- The provider puts a device called an ultrasound transducer on your belly. It’s attached to your belly with straps. This device sends the fetal heartbeat to a recorder. The fetal heart rate is displayed on a screen. It may also be printed on special paper.
- The provider may put another device over the top of your belly with a belt. This is called an external tocodynamometer. It can record the patterns of contractions.
In some cases, you may need internal fetal monitoring for a more accurate reading of the fetal heart rate. This can only be done if your bag of waters (amniotic sac) is broken and your cervix is partially open (dilated). The provider puts a small, sticky pad called a fetal scalp electrode through the open cervix. It’s attached to the baby’s scalp. The electrode is attached to a wire. The wire sends information about the baby’s heartbeat to a computer.
What happens after fetal monitoring?
After external fetal monitoring, the provider removes the straps and wipes the gel off your belly. After internal fetal heart rate monitoring, the provider checks your baby’s scalp and cleans it where the electrode was stuck.
Before you agree to the test or the procedure make sure you know:
- The name of the test or procedure
- The reason you are having the test or procedure
- What results to expect and what they mean
- The risks and benefits of the test or procedure
- What the possible side effects or complications are
- When and where you are to have the test or procedure
- Who will do the test or procedure and what that person’s qualifications are
- What would happen if you did not have the test or procedure
- Any alternative tests or procedures to think about
- When and how will you get the results
- Who to call after the test or procedure if you have questions or problems
- How much will you have to pay for the test or procedure