15 Crazy Facts About The Fetal Heartbeat

The first time a mom-to-be hears her child's heartbeat is life changing. Everything feels more real. It's very apparent suddenly that she is carrying a real human life inside her. The scene has played out on hundreds of TV shows and movies, but the reaction is always the same; shock, awe, and amazement. Something about hearing that wonderful sound and knowing in that instant that a woman's child is healthy is amazing.

The fetal heart is an amazing thing for a variety of reasons. For example, the rate at which it develops into such a complex organ is astounding. The fact that a fetus gets excited as witnessed by their increased heart rate is also amazing. A lot goes into the fetal heart and there happens to be a lot of old wives' tales floating around about fetal heart development. For example, can the heart rate of a baby in utero really predict gender? Read this list to find out some things most people probably didn't know about the fetal heart and the things that can affect it.

15 It Starts Beating At 21 Days After Conception

People measure pregnancies differently. Most doctors go off of the first day of a woman's last menstrual cycle. However, ovulation usually occurs around 15 days after the first day of a woman's last menstrual cycle. That means conception typically occurs two weeks into the cycle. It's kind of confusing but makes sense to calculate this way since most people cannot pinpoint exactly when their child was conceived, so measuring from the first day of the last menstrual cycle creates a uniform way in which providers can measure all pregnancies.

The crazy thing about the fetal heart relating to conception is that it starts beating just 21 days after conception! So in 21 days, the sperm will travel and fertilize an egg then the fetus will burrow into the uterine lining and begin developing incredibly rapidly. Within those short 21 days, the fetal heart will begin beating though not as regularly as it will later in pregnancy. It's astounding that so much development can occur within just three weeks.

14 The Average Rate Is High For Adults

The average adult heart rate varies with age, gender, and activity level but generally speaking it is about 60-100 beats. Obviously, an adult heart rate varies greatly for a sedentary person versus an experienced fitness guru. Most physically fit people have a resting heart rate of 40-60 beats per minute. In fact, some physically fit people have an issue with heart rate monitors setting off alarms during surgery since the heart rate of these people can get so low.

A fetus' average heart rate is usually much higher than adults. In fact, some people listening to their child's heart on the monitor for the first time become worried because it sounds like the heart is beating a mile a minute. A fetus's heart rate is on average 120-170 beats per minute, sometimes it gets even faster than that. Towards the end of pregnancy, a fetus heart rate will drop to about 130 beats a minute, which is significantly lower than 170, but still far higher than adults (unless of course, that adult is running up stairs).

13 It Doesn’t Predict Gender

When a couple first hears they are expecting they are ecstatic, especially if they tried to conceive for an extended period of time. However, as excited as they are they will soon find out pregnancy is about patience. First parents usually wait until they are 12 weeks pregnant to tell everyone, but then as soon as they do everyone wants to know the gender of the baby. However, most doctors will not determine gender until about 18 weeks into pregnancy.

The waiting period for new parents is hard. They want to decorate the nursery, buy baby clothes, and pick out names, but all that is nearly impossible until they know if they are having a boy or girl. In these cases, many people will turn to old wives tales to find out the gender. One such old wives tale is that parents can predict the gender of their little one based off of the baby's heart rate during ultrasounds. The tale basically states that heart rates of 140 and higher mean it's a girl and lower means it's a boy. Unfortunately, plenty of research studies have proven this "test" inaccurate. However, if parents just absolutely can't wait there is a new noninvasive blood test that uses the mother's blood (not amniocentesis) to predict the baby's gender at just 10 weeks.

12 It Can Be Seen And Heard

In life, visual confirmation is usually what most people want when it comes to trusting something. That is not true for the fetal heart. Everyone wants to hear that precious sound and know their little one is okay and thriving. Early pregnancy can be an extremely difficult time for some people, especially those at high risk for miscarriage. These parents usually know once a heart is pumping that chances of miscarriage lowers. Even without auditory affirmation, doctors can ease new parents minds by showing them the heart beating.

A baby in the uterus at 6 weeks into pregnancy is only about a quarter of an inch. The baby's heart is even smaller. For a doctor to find the baby and the heartbeat during a vaginal ultrasound is already difficult, but to actually hear such a tiny pinpoint is impossible. The good news for anxious parents though is the doctor can usually see and show the beating heart to parents even if it's too little to be heard.

11 Maternal Fitness Matters

Fitness is important for everyone, not only for the mental reprieve from the day but also, and most obviously, for physical health. In fact, it has been proven that people in relationships can even benefit if one of the partners starts taking their health more seriously. It has also been anecdotally and factually proven that parents' fitness levels and attitudes will affect their children’s.

What most people aren't aware of is the fact that maternal fitness affects the baby positively and not just because the mother is healthy. In fact, when mom works out her baby gets a workout and the benefits that go with it. When moms work out, her heart rate rises, but the shocking part is so does the baby's. Not only does the baby's heart rate rise during mom’s run but the benefits are long lasting just like when adults work out. In fact, fetal hearts of mothers who work out are stronger with a lower resting heart rate, which is a generally accepted sign of heart strength.

10 It Takes A Special Ultrasound To Hear It

New mothers dream of hearing their precious baby’s heart beating. It is a magical moment that verifies the new life inside of them and shows that the baby is alright. Most women wait with intense anticipation to hear those precious sounds and cannot wait for the first ultrasound. Those women may be surprised when they finally get that first ultrasound.

While women dream of the first ultrasound being just like the movies, they may be shocked when they arrive at the first appointment and the doctor asks them to remove their pants. That's right the first ultrasound is usually done transvaginally. That is because the baby is far too small to find through a regular ultrasound so the tech will need to be as close as possible to find the baby.

In fact, to hear the fetal heartbeat before 10 weeks, transvaginal is often the only possible way. This might shock new moms, but the seasoned pros understand what that first ultrasound may entail and still find it worth it to hear that precious thump thump of a baby’s heart.

9 Baby Will Often Hide From The Doppler

Kids are squirmy, any mother or even babysitter can attest to this fact. They are always on the go, even sleeping children are known to roll right out of bed or kick in their sleep. However, most people don't realize these wiggles start before the baby even exits the uterus. Babies manage to wiggle, flip, and even hiccup all while inside of mom.

When an obstetrician or radiographer is trying to check on the baby’s heart, the baby can make that difficult. In fact, just like babies react to loud noises in utero or even when their mother touches her belly, the baby will also react to the Doppler pushing them. The baby often times will actually squirm away from the Doppler making it extremely difficult to hear the baby's heart, especially for more than a few seconds at a time. For some mothers that rush to the hospital for fear of their baby not moving, as soon as they get to the hospital and put the monitoring belt on, the baby will squirm right out of the way, confirming that the baby is, in fact, fine and probably was just napping.

8 A Stethoscope Can’t Hear It Until 20 Weeks

Before the home pregnancy test and sonogram came along, people had it rough when it came to pregnancy. Number one, they didn't have home pregnancy tests so if they had irregular cycles they might not know until the baby started moving. Two, there weren't many tests a doctor could do to make sure the baby was healthy. Doctors used to just put their ear up to a woman's belly to listen for the fetal heartbeat. Which was probably somewhat awkward for both the doctor and patient. But then in 1816, a guy named René Laennec invented the stethoscope, however, it still was not commonly used for quite a while.

Nowadays the stethoscope is extremely common for both doctors and nurses. It is used to listen to lungs, pulses, and heart beats. In fact, the stethoscope can even be used to listen to a fetal heart. Unfortunately, a stethoscope won't be able to clearly identify the babies' heartbeat until around the 20th week of pregnancy. But after the 20th week of pregnancy, most obstetric doctors will prefer their stethoscope over the Doppler for fetal heart listening.

7 Parents Can Listen At Home

As mentioned previously, listening to a baby's heartbeat in utero is an amazing and calming thing. For mothers who have high-risk pregnancies or have had prior miscarriages, being able to check in on the baby any time is wonderful sounding. In today's modern world certain companies have created at home Dopplers for expectant moms to listen to the baby at home.

Listening to baby’s heart and knowing they are okay without having to go to the doctor sounds great. However, it is a little misleading to think it’s as great as it sounds. Every good thing seems to have a drawback. That is true of at home Dopplers, too. Dopplers, for example, can only be used after a certain time into the pregnancy, but the real drawback is most people aren't trained to use them. In fact, most expectant mothers will sit there feeling ecstatic about listening to their infant's heart when in reality they are listening to their own pulse. This can be dangerous because if a mother doesn't feel her baby is moving she may listen for fetal heartbeats and feel relieved only to hear her own pulse and not consult her doctor when she should.

6 Ibuprofen Can Slow It Down

Proper fetal heart development is obviously the most important part of fetal development. Without a heart, nothing can live and if the heart doesn't develop properly life is at risk. That is why hearing a fetal heartbeat is so exciting and relieving to so many parents. But unfortunately, some women may be putting their baby's heart development at risk with a very common over the counter medication.

Ibuprofen or Motrin as some people call it, poses a significant risk to a developing fetus' heart. Not just in early pregnancy, but particularly in the third trimester. In fact, research studies have shown that it may cause the fetal heart to stop developing as it should and can even lead to the death of the infant or cause too much bleeding during labor for the mother. So what can an expectant woman take if not ibuprofen for aches and pains during pregnancy? It has long been studied that Tylenol (acetaminophen) is safe for use during pregnancy.

5 Doctors Look For Defects As Early As 11 Weeks

Even if a new mother does everything right, heart defects are the most common form of birth defect, with approximately 1 percent of all babies born in the US having congenital heart disease of some sort (congenital means present at birth). The good news is that with modern medicine, most of these situations will either correct on their own or can be fixed with surgery. A key to effective treatment and the safety of the new baby is early detection and preparedness. One way to make sure that any needed treatments are provided is a fetal echocardiogram.

A fetal echocardiogram is when a special form of camera called a transducer is used to send ultrasonic sound waves into the mother’s abdomen. These sound waves bounce off everything inside her, including the baby. By carefully reading the soundwaves, computers are able to determine how quickly blood is flowing through the baby’s heart and whether it’s flowing through all the correct parts of the heart. If this sounds similar to an ultrasound, that’s because the two technologies are very similar, with the fetal echocardiogram simply being more precise. Doctors can then use these readings to determine if there is any cause for concern. Most of these tests are done at only 11 weeks into the pregnancy.

4 Acne Meds Can Hurt A Fetal Heart

The leading cause of birth defect-related infant death is congenital heart defects. Most mothers now know not to smoke, drink alcohol, or do any illicit drugs during pregnancy because these are all linked to birth defects in babies. The issue that is currently causing heart defects in babies is the things moms don't know that can cause harm. For example, Accutane, which is an acne medication.

Many expectant moms may struggle with acne and have prescriptions for treating it. What many expectant moms may not know is that certain acne medications can cause serious and life-threatening heart defects for the baby. The other issue is people that take this medication without intending to become pregnant or they are at first unaware of their pregnancy and could, therefore, be harming the baby's heart development without even knowing it.

3 The Sound Of It Can Soothe Baby After Birth

After birth, babies are often fussy because they miss their perfect environment. In utero, babies have the perfect temperature, the right snuggle, and perfect background noise. Babies even learn to enjoy the sounds they hear constantly. Often times these sounds are their parents' voices, their mother's heartbeat, and even their own heartbeat.

Thankfully for parents everywhere, there are certain soothing sounds that are similar to the sounds heard in utero. Baby stores even carry “white noise” machines to soothe infants. One of the most interesting toys like this is the “my baby’s heartbeat bear.” This toy can have ultrasounds of the fetal heart beat uploaded onto it and can then be played for the baby after birth to soothe them.

2 It Increases During Contractions

Everybody (except maybe husbands) understand that labor hurts. Seriously no matter what pain management or breathing techniques a person has been given or taught, it will hurt. A mother literally pushes a human being out of her and the organ that sustained said human being during that time. It is not easy.

What most people are unaware of, however, is that the baby probably doesn’t enjoy it either. The baby gets slowly pushed and pulled out of their perfect environment. After all the pushing and pulling they are then in a loud, bright, confusing world. During labor, doctors need to know not only how mom is doing, but also how the baby is handling the labor. This is done by monitoring the fetal heart and seeing how the baby is coping with labor. In some cases, babies may not be able to handle labor and will have to be delivered via cesarean because of their heart rate not staying in the normal range for labor.

1 It’s The Best Sound In The World

It has been said before, but it still rings true. Those firsts in life are amazing, first kiss, first car, and first love. They are all great. However, none are quite as magical as hearing the sounds of baby's heart and a mother knowing not only has she created life but that her precious baby is doing well. Hearing those heartbeats is proof to the parents that there really is a new person growing in there.

For many fathers, it is the first time the entire pregnancy, “I’m going to be a father!” thing really sets in. Hearing the beating heart of his child and seeing the sonogram images makes it suddenly all very real. Not that he didn’t believe it before, but it was a distant reality and something only the mother was truly experiencing up until that point. Hearing those first little beats of a heart are life changing and can change any person into a parent.

References: Radiopaedia.org, InGender.com, PrenatalGeneticsCenter.com, NYTimes.com, BabyDoppler.com, MerckManuals.com

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