Is there anything more precious than hearing your baby’s heartbeat in the womb?
As a sign of life, a baby’s heartbeat is anticipated during ultrasounds and is often one of the first moments when pregnancy begins to feel “real” to new parents. That healthy heartbeat provides feelings of security, peace, and excitement. It’s no wonder we moms want to hear our baby’s heartbeat whenever we can.
Thanks to the emergence of commercial fetal Dopplers, families can do so whenever they’d like, in the convenience of their homes. However, nothing is more important than ensuring your baby stays healthy and strong. So, before using a fetal Doppler, you should consider whether it’s safe.
As we’ve had these same concerns, we researched this topic extensively, and we want to discuss fetal Doppler safety. We’ll also look at some important facts about monitoring your baby’s health and heartbeat throughout pregnancy.
Understanding Your Baby’s Heartbeat
As we discuss fetal Dopplers, it is good to understand how your baby’s heart works.
The growth of a baby’s heart is miraculous. Your baby’s heart starts beating at approximately five weeks gestation. When the heart starts beating, it may be slow, around 100 beats per minute (bpm). From this point on, the heartbeat will fluctuate depending on your baby’s gestational age.
By nine weeks, the average heart rate is 175 bpm and will likely fall between 120 and 180 bpm throughout most of your pregnancy. During the last ten weeks, the heartbeat will begin to slow (1).
If you compare this to an adult’s average heartbeat, which is 60 to 100 bpm (2), you’ll see that babies’ hearts beat much faster.
Generally, when we hear about an elevated heartbeat, we start to worry. With babies, it is an entirely different story. This fast heartbeat is completely normal and shouldn’t cause concern.
What Is a Fetal Doppler?
A fetal Doppler is a small, handheld machine that detects and emits the sound of your baby’s heartbeat (3).
To use a Doppler, you hold one end in your hand, where the controls are located, and the sound is emitted. The Doppler apparatus is generally attached to this unit with a cord.
A gel is applied to the Doppler monitor to allow it to move freely. The Doppler is placed onto your stomach and moved about until you hear the heartbeat.
Along with your baby’s heartbeat, a fetal Doppler can also pick up any other sound waves inside your body, including your own heartbeat.
Fetal Doppler vs. Ultrasound?
You may be surprised to learn that ultrasound isn’t a machine. Ultrasounds are sound vibrations so high human ears can’t hear them. During an ultrasound visit, your doctor uses an ultrasound machine to capture visual and audio recordings of your growing baby inside the womb.
The ultrasound machine is operated by a technician and produces the image and provides the sound. A fetal Doppler differs in that it can only produce sound when placed very close to the source.
Are Fetal Dopplers Safe?
The answer to this question is complicated. A fetal Doppler doesn’t pose a major threat to your child when used by a trained professional. However, medical professionals strongly advise against using fetal Dopplers at home, and we have to agree with them.
When we look closely at the problems fetal Dopplers can pose, we realize they are not a good idea.
We can summarize our concerns with fetal Doppler safety in five points.
1. Lack of Training
On the surface, finding and listening to your baby’s heartbeat may seem simple. Don’t you just have to take the Doppler, place it on your stomach, and listen? This may be the start, but the interpretation of what you hear is essential.
Health care professionals, including doctors, nurses, and midwives, train extensively to learn how to use ultrasound equipment properly. They know what a normal baby heartbeat sounds like and can use that knowledge to diagnose any problems.
Moms using fetal Dopplers at home do not have the benefit of this experience and training.
2. Extra Stress
Because you often do not know how to analyze your baby’s heartbeat, it is easy to become scared. What if you can’t find your baby’s heartbeat simply because your child has moved positions? What if the speed of your baby’s heartbeat freaks you out, even though it is normal?
Fetal Dopplers cause moms stress, and stress is not good for your baby. High stress levels have been shown to increase the risk of premature birth, low birth weight, and a lower immune system in mother and child (4).
3. Missed Warning Signs
In one tragic case, a woman became concerned when she noticed her baby had stopped moving. She used a fetal Doppler, heard a heartbeat, and felt reassured. However, when she went to the doctor the next day, she learned her baby had died.
It turns out she may have just heard her own heartbeat instead of her child’s. Unless a person is trained to use Dopplers, they may still miss warning signs while using the equipment. Trusting your gut is essential.
4. Risk of Wave Overexposure
According to the U.S. Food & Drug Administration, the effects of excessive tissue heating and cavitation caused by ultrasounds are unknown. In fact, the FDA recommends getting ultrasounds only when medically necessary and as supervised by a health care professional.
Many who use fetal Dopplers use them for far too long, not knowing long-term tissue heating could potentially be dangerous.
5. Inaccurate Results
At-home fetal Dopplers are often less efficient than ultrasound machines. Considering the major cost difference between the two, this is hardly surprising.
When it comes to listening to your baby’s heartbeat, you want accurate results. Fetal Dopplers don’t have the level of technical quality essential for a pregnancy product.
If You Decide to Use a Fetal Doppler
We advise all mamas to stay away from at-home fetal Dopplers. However, if you’ve made up your mind to try it out, we strongly urge you to keep the following recommendations in mind:
- Limit the Exposure: Do not use the fetal Doppler for more than a few minutes.
- Ask for Training: Look for a health care professional in your area to help you learn to use your fetal Doppler. However, be warned, there is a good chance they’ll advise against using one at home.
- Don’t Analyze: Do not try to use a fetal Doppler to assess your baby’s health on your own. An incorrect assumption about what you are hearing can be dangerous.
- Contact a Doctor: Trust your gut. Regardless of what you may or may not hear on a fetal Doppler, talk with your doctor if you have any concerns about your baby’s health.
If you would like to be more involved with your pregnancy, we suggest learning more about a midwife or doula. They will talk about your pregnancy as much as you need.
This could be a great option for moms who want to feel more empowered as they monitor their pregnancy.
How Can I Know if My Baby Is Healthy During Pregnancy?
One of the reasons moms use fetal Dopplers is to ensure their baby is healthy during pregnancy. Fortunately, there are more effective ways to do this.
1. Fetal Movements
Fetal movements, also known as quickening or kicks, tell you your baby is developing properly. While you may begin to feel movement as early as week 20, the movements become more pronounced by week 25. As you near your due date — approximately 36 weeks — your baby’s movements will slow down (5).
You can count the movements to determine if your baby is healthy. The American College of Obstetricians and Gynecologists recommends getting into a comfortable position when your baby is active, generally after meals. Then count the number of times you feel your baby move or kick. You should feel at least ten movements within a two-hour period.
If you don’t feel at least ten movements in two hours, call your doctor for a checkup.
2. Belly Measurements
Grab the measuring tape and see how big your belly is growing. If you do it properly, you’ll be doing more than just measuring your belly; you will actually be measuring the height of your uterus. The uterus emerges from your pelvis at twelve weeks, so you can try this after that point. Follow these steps to measure yourself at home:
- Find your pubic bone. It is just above the pubic area and should feel hard when you press down gently.
- Find the top of your uterus, known as the fundus. Gently massage the area below or above your belly button. After 20 weeks, the fundus should be above your belly button. The fundus should feel like a ridge beneath the skin.
- Using a measuring tape, measure from the pubic bone to your fundus in centimeters.
The number of centimeters should correlate to your baby’s gestational age within 1 to 4 centimeters. So, if you are 28 weeks, your measurement should read between 24 and 32 centimeters. If you’re unsure if you’re doing it properly, ask at your next OB appointment.
It is important to note there may be some variations to this measuring system depending on your baby’s size and how many babies you are carrying.
3. Go to the Doctor
As a mama, you’ve got some natural instincts about what is normal and what isn’t. If you feel nervous about your baby’s health during pregnancy for any reason, contact your doctor. Your health care provider will be able to perform diagnostic tests to ensure your baby is okay.
Even just a phone call can help ease your mind and get you some answers. Always trust your instincts. It is better to be safe than sorry.
There are other safe ways to monitor your baby’s health and growth while in-utero. We recommend you use these methods instead of regular fetal Dopplers.
All measurements aside, the most critical factor is your intuition and your experience. If you feel something is wrong, call your OB provider. Women are experts in understanding their bodies and their babies.
Editor's Note:Caitlin Goodwin, MSN, RN, CNM
Pregnancy Warning Signs
If you experience any of the following warning signs during pregnancy, contact your health care provider immediately (6):
- Vaginal bleeding or leaking.
- Intense cramps or muscular convulsions.
- Severe abdominal pain.
- A decrease in your baby’s movements.
- Dizziness or fainting.
- Inability to eat or drink.
- Fever >100.4 degrees Fahrenheit.
Any of these signs could signal your baby is in distress and you need to see an OB provider. Every woman is unique and has different health risks. When you learn you are pregnant, discuss these risks with your doctor or midwife, and learn the warning signs specific to your situation.
The Bottom Line
Fetal Dopplers are encouraged by some as a way to enjoy your baby’s heartbeat and learn about their health. However, unknown consequences, lack of training, and inaccurate results can lead to a lot of trouble. That is why we feel at-home fetal Doppler usage is unsafe.
If you decide to use a fetal Doppler, we strongly suggest you contact a health care professional to help you.