When Can You Hear Your Baby’s Heartbeat?

If you’re eager to dance to the rhythm of your baby’s heart, let’s find out when you can expect to hear it—and cover everything else there is to know about how his heartbeat will develop.

The heart is one of the first organs to develop. Its formation begins just 3 weeks into your pregnancy. However, you probably won’t be able to hear it before your 12th week of pregnancy. 1

Your baby’s heart: a developmental timeline

Here’s a timeline of the key events in your baby’s cardiovascular development:

• Weeks 3–4: Your baby’s heart begins developing during the third week, and by the fourth week, it starts pulsing in rapid and irregular contractions. 2
• Week 6: Though your baby’s heart is still not fully formed, your doctor can detect cardiac activity known as a “flutter” (though you won’t be able to hear it yet). At this point, a group of cells within your baby’s “proto-heart” begin firing electrical signals, causing those first flutters. 3
• Weeks 7–9: Your baby’s heart continues to develop, with the chambers and valves beginning to take shape. By week 9, his heart rate reaches around 170 bpm before beginning to slow. 2 Your baby’s cardiac activity will count as a genuine fetal heartbeat once he develops the chambers of his heart, around week 10. 4

Your baby uses his heart differently in your womb than he will after birth.

Because he can’t use his lungs to breathe just yet, your placenta sends oxygenated blood (and nutrients) to him through the umbilical cord.

This blood travels through three passages (known as “shunts”) in his body. Think of these as shortcuts that bypass your baby’s lungs and liver, which aren’t fully operational yet, to circulate blood throughout his system. The three shunts are known as the ductus arteriosus, ductus venosus, and foramen ovale. 5

When your little one comes into the world, his organs will start functioning normally, and these shunts will disappear.

Your baby’s heartbeat and the odds of miscarriage

You’ll be glad to know that once you hear your baby’s heartbeat, statistically, the chances of miscarriage drop.

One study shows that once your baby has a heartbeat (usually around 6–7 weeks in), your risk of miscarriage drops to about 1.6%. 6

As you’ve probably gathered, it’s normal for your baby’s heart rate to be faster than an adult’s (potentially up to twice as fast).

After hitting around 170 bpm at 9 weeks, your little one’s heartbeat will slow to around 120–160 bpm during the second and third trimesters. 7 During labor, it should stay between 110 bpm and 160 bpm. 8

Here’s how your doctor will measure your baby’s heartbeat throughout your pregnancy:

Doppler

A machine called a Doppler device can pick up your baby’s heartbeat. This will likely be the first time you’ll hear his heart (during a scheduled appointment with your OB).

Fetal heartbeats are sometimes audible by Doppler around 10 to 12 weeks, but sometimes it takes a bit longer—up to 14–16 weeks, particularly when the expectant mom is obese or has a retroverted (tilted) uterus.

At-home Doppler devices

Some parents can’t wait for this appointment and buy home-use Doppler devices in the hopes of hearing their baby’s heartbeat on their own.

However, experts advise against this. At-home Doppler devices are much less sophisticated than the ones doctors use. They’re less accurate, and can mistakenly pick up sounds from your own heart or your placenta.

Moreover, using a Doppler correctly requires training. Without it, the odds are good that you won’t hear a heartbeat at all (something that often causes parents to worry

Ultrasound

You’ll also get to hear your baby’s beating heart in some of your ultrasounds. You’ll have several of these scans throughout your pregnancy:

• Early transvaginal ultrasound: This detects initial cardiac activity, which, as mentioned, starts when you’re around 6–7 weeks pregnant. 9 This may be visible as a faint “flickering,” but you won’t actually get to hear a heartbeat at this stage.
• Anatomy or gender scan: Your OB will conduct a more detailed ultrasound when you’re around 20 weeks pregnant. You’ll then be able to see your child’s heart chambers more clearly (and, incidentally, find out his sex—one of the big appeals of the anatomy scan). 10
• Fetal echocardiogram: If you have a family history of heart defects or other indications, your OB might suggest a fetal echocardiogram (a specialized heart ultrasound). If so, you’ll usually get this test between 18 and 24 weeks. 11 12

Note that your baby’s heartbeat has nothing to do with his sex and isn’t one of the signs of having a boy or girl. 13 Some people claim that baby boys and girls have different heart rates, but this is a myth.

Stethoscope

What about hearing your baby’s heartbeat with a good, old-fashioned stethoscope? While this is one of the most exciting ways to hear your baby’s beating heart, you’ll need to be patient.

Usually, you’ll be able to hear his heartbeat with a stethoscope around week 20 of your pregnancy.

It’s understandable to be worried if your OB can’t detect your baby’s heartbeat. However, that’s not always a sign that something’s wrong.

Here are a few possible reasons why your doctor can’t pick up the pitter-patter of your little one’s heart just yet:

• Gestational age: You might have your due date wrong—meaning it could just be too early to detect a heartbeat.
• Body size: If you’re obese, it can be harder to detect your baby’s heartbeat.
• Uterine position: If you have a tilted uterus, also known as a retroverted uterus, this can also make detecting your baby’s heartbeat more challenging.

If your OB can’t detect a heartbeat during your initial appointment, they’ll probably schedule you for a follow-up appointment to recheck it in a week or two.

When can failure to detect a heartbeat indicate a problem?

To reiterate, not hearing your baby’s heartbeat isn’t necessarily anything to worry about, especially in the early days. However, there are times when it can signal an underlying issue.

Miscarriage

If you can’t hear your baby’s heartbeat, it’s (unfortunately) possible that you had a miscarriage. This is more likely if you also experienced other miscarriage symptoms, such as: 14

• Vaginal bleeding/spotting (although occasional blood in your pregnancy discharge can also be normal)
• Severe cramping or belly pain

If you experience any of these symptoms, speak to your doctor immediately.

Ectopic pregnancy

An ectopic pregnancy is a type of nonviable pregnancy that occurs when a fertilized egg implants outside of the uterus, usually in the fallopian tube. 15 The embryo will be unable to survive.

An ectopic pregnancy is a serious condition that requires immediate treatment. Although your body may absorb the embryo without intervention, there’s a chance it will continue to grow, eventually rupturing your fallopian tube. This can cause a life-threatening hemorrhage.

The symptoms of an ectopic pregnancy can sometimes have similar symptoms to a miscarriage. Speak to your doctor immediately if you have any of the following symptoms: 15

• Severe belly pain (commonly on one side)
• Vaginal bleeding (unrelated to your period—if you’re still menstruating, you don’t have an ectopic pregnancy)

You can support your little one’s heart health by:

Taking your prenatal vitamins

Don’t skip the prenatal vitamins. They provide essential nutrients for your baby’s development.

Folic acid, one of the key prenatal vitamins, is mainly necessary to prevent nervous system defects, but some studies show that it may prevent your baby from developing heart defects, too.

Quitting smoking or vaping

Smoking or vaping while pregnant will cause serious issues for your baby. It restricts the amount of oxygen he has access to in the womb, meaning his heart will need to beat much harder than normal. 16

These activities also increase the chances of stillbirth. Even if your baby’s relatively healthy at birth, smoking while he’s in the womb could make him more prone to becoming asthmatic later in life. 17

Avoiding alcohol

As you may already know, you should avoid alcohol entirely during pregnancy. Drinking alcohol leads to a number of fetal alcohol spectrum disorders (FASDs), which in turn can cause: 18

• Low birth weight
• Developmental delays
• Visual or hearing impairment

Drinking when you’re pregnant also puts your baby at risk of poor growth, decreased muscle tone, and other problems. 19

There are few moments as exciting as hearing your baby’s heartbeat for the first time. You may find it hard to wait, but do your best to be patient and think of it as something to look forward to. As always, give your doctor a call if you have any concerns or problems.