The very first sign that there is life developing inside you is the heartbeat. The heartbeat is one of the factors that confirms pregnancy. The chances of miscarriages also reduce in pregnancies where the fetus heartbeat is detected in time. For this reason, your doctor may suggest an early ultrasound to check your baby’s heartbeat. It is a magical experience to hear the little lub-dub of your little one’s heart and is a moment to cherish.
As a newly pregnant woman, this ultrasound appointment can be both scary and exciting for you. So many apprehensions and worries. If this is your first pregnancy, you may also not be very sure what to expect and what the norm is. Through this article, we try to explain some pointers such as when the heart starts beating, How the heart and circulatory system of the fetus develop, normal fetal rate, etc. Scroll down to learn more.
When Does Your Baby Start Having a Heartbeat?
A fetus, or better to say an embryo, starts having heartbeats from 5 to 6 weeks of its life. So if you do a vaginal ultrasound on the 6th week of pregnancy, then you can see the first sight of your baby (the fetal pole) and hear the heartbeats.
When Can You Hear Your Baby’s Heartbeat?
The heartbeats of the fetus can be heard as early as 6 weeks of gestation by vaginal ultrasound. But as it is too early, you may sometimes not hear fetal heartbeats. Then your doctor will ask you to do the ultrasound one or two weeks later.
There can be other possible reasons for not hearing heartbeats instead of despite you having a normal pregnancy. Delayed hearing of the heartbeat of your little one can happen when you have
- A larger abdomen
- A retroverted uterus
But it is not important to go for an early ultrasound just to check the fetal heartbeat unless you have possible risks in pregnancy such as.
- A prior miscarriage
- History of prior complicated pregnancy
- Pregnancy at a late age
- Serious medical conditions like diabetes or high blood pressure.
Otherwise, in general a gynecologist recommends the first-trimester ultrasound in between 11 and 14 weeks. And by that time the fetal heart will also develop considerably. So you will be able to hear the clear heartbeats of your baby.
[Read : What Prenatal Tests Are Done in The First Trimester]
What is the Normal Fetal Heart Rate?
The fetal heart rate changes as the heart develops. At 6 to 7 weeks, the fetal heartbeat will be between 90-110 bpm. And during 9 to 10 weeks, the heartbeat will reach up to 140-170 bpm. So, on average, the fetal heart rate or FHR stays within 120 to 160 bpm or beats per minute. The FHR initially increases from the 6th to 10th week and then decreases and stabilizes at one point in pregnancy.
Determining Your Pregnancy Weeks With FHR
By measuring the FHR, your doctor can determine the actual duration of your pregnancy. For instance
- FHR around 110 bpm means 6 weeks of pregnancy.
- 170 bpm means 9 to 10 weeks of pregnancy.
- FHR decreases after that and by 14 weeks it turns to 150 BPM.
- 140 bpm by 20 weeks of pregnancy.
- Stable at 130 beats per minute for the rest of the weeks.
A fetal heart rate usually stays regular and in a rhythm, but occasional beat to beat variation is normal too.
Abnormalities in FHR
But if the FHR is abnormally low, such as below 100 bpm in the first trimester, then the condition is called Fetal Bradycardia. On the other hand, abnormally increased FHR such as 170 to 220 bpm is termed Fetal tachycardia.
And an increased, irregular fetal heartbeat is called Fetal Tachyarrhythmia. Here, the FHR can reach up to 230 to 280 BPM.
When Can You Hear the Fetal Heartbeat With Doppler?
A Doppler is an ultrasound device to check fetal heart rate. You can check your baby’s heartbeat with a Doppler from around 8 weeks of pregnancy. But checking heartbeat with a Doppler this early may not be so fruitful. Thus, doctors prefer to use Doppler after 12 weeks.
Also, there are home doppler devices that you can purchase to check your baby’s heartbeat at home whenever you want. But these home Dopplers are not fully reliable. As you are not a trained professional you may get confused between the sound of your own heart or pulse and the sound of your baby’s heart.
[Read : Doppler Scan During Pregnancy]
When Can You Hear the Fetal Heartbeat With a Stethoscope?
To use the stethoscope for fetal heartbeat monitoring you will have to wait a bit longer. At around 18 to 20th week of pregnancy, your doctor can put a stethoscope on your baby bump to hear the heartbeats of your baby.
The chest piece of the stethoscope can capture minimal sound and amplify it. You can hear your baby’s heartbeat by putting the tube attached to the chest piece in the ear.
Thus your doctor will use a stethoscope once you reach the middle of your pregnancy. You can even buy a stethoscope from any medical shop and tell your hubby to check your baby’s heartbeat. It will definitely be a memorable moment in your life.
To check a fetal heartbeat with a stethoscope, you will have to go to a quiet room and lie on your back. Then you will have to touch and feel the baby’s back and place the chest piece there. Then you can slowly move the stethoscope around your belly to get a clear sound.
How Do Your Baby’s Heart and Circulatory Systems Develop?
It takes time between 5 and 10 weeks for the heart and the circulatory system to develop fully.
- In the fifth week of gestation, the heart forms with only two tubes that fuse and create a trunk with four branching off tubes.
- In the 6th week, the basic heart tubes loop and form an S-shape and create an area for the ventricles.
- At 7th week the atria and ventricles separate and develop.
- At 8th week the valves that regulate blood circulation between the atria and ventricles form.
- In between the 9th and 10th week of pregnancy the aorta and pulmonary vein form. And by the end of the 10th week, your baby’s heart is completely ready.
To be able to hear your baby’s heartbeat for the first time is the best thing ever. Another thing is that you don’t have to wait much for it. But do not panic if you cannot hear it during the early ultrasound. Let your doctor advise you according to the situation.
[Read: Is It True That Fetal Heart Rate Can Predict The Baby’s Gender?]
FAQ’s
1. How Can I Check My Baby’s Heartbeat at Home?
You can buy a stethoscope or a Doppler to check your baby’s heartbeat at home. Doppler is helpful in the first trimester. On the other hand, you can use a stethoscope after 20 weeks of pregnancy. But do not make any decision based on these home tests as you are not a professional. Let your doctor do the job.
2. Can a Baby’s Heartbeat Indicate Gender?
You may have come across this old wives tale but it has no scientific value. These tales say that a girl baby has more fetal heart rate than a boy baby. The heart rate of the fetus changes depending on the duration of pregnancy. It has nothing to do with the gender of the baby.
3. Is it Normal For No Heartbeat at 7 Weeks?
Yes, sometimes you cannot hear a heartbeat during the 7th week’s ultrasound. It is too early to be picked up. Your doctor will ask you to come for another ultrasound in a week or two.
Read Also: 5 Different Phases Of Fetal Lung Development
