15 Crazy Facts About How Alive The Baby Is In The First Trimester

A baby is nothing short of a miracle. When egg and sperm meet, someone cells converge and split and divide and multiply, and pretty soon a tiny little person forms in a mother's womb.

It takes just days for a heart to beat and weeks for the lungs to form. The little one grows and develops from a size that could only be seen on a microscope to the size of a prize fish in nine months, and the milestones in between are absolutely amazing. Right from the beginning, there is a little life unseen on the outside but changing everything from within.

During the first trimester, the time from conception through the 12th week of gestation, there are very few signs of the life inside a woman that can be seen from the outside. For a first-born child, especially, there is little to no baby bump, and the mom-to-be won't feel her baby moving inside her for weeks. But the signs of life are there almost immediately, and while there is the possibility that the pregnancy can end in miscarriage, the tiny being inside is already a miracle.

Here are 15 crazy facts about how alive the baby is in the first trimester.

Continue scrolling to keep reading

Click the button below to start this article in quick view

Start Now

15 Science Lesson

According to scientists there are several characteristics that determine a living thing as opposed to a non-living thing. A living thing is made up of cells, and it requires energy to survive. A living thing has the ability to metabolize that energy (or in human terms, digest), and it responds to stimuli and adapts to its environment. A living thing has the ability to respire or breath, and the ability to move. And finally, a living thing has the ability to grow.

Those are the differences between a plant and the soil that it lives in, between a real live grizzly bear and a teddy bear. And if you think about a fetus, everything applies, although its respiration goes through the mother and the umbilical cord until it is born and it can take a bit for the reproductive organs to be ready for action. Of course, humans and plants and animals aren't the only living things in the natural world. Some, like a fetus, are microscopic. Take, for example a bacteria or a protozoa. Science proves that you don't need to be big to be alive.

14 Growth

One of the most obvious criteria in the definition of a living thing that applies to the first trimester is the ability to grow, and it may not seem like much but to grow from one or two cells to 1 ounce in three months is actually just about the largest percentage gain that a baby will ever make in such a short period of time.

Not only does the baby grow exponentially each day during the first trimester, those cells are dividing into different organs and tissues, and the shape goes from a sphere to a tube to a strange shape with a tale to looking like a tiny little human all in less than a dozen weeks.

The growth of a fetus in the first trimester is truly astounding when you think about it, and it's just one of the many signs of how alive the baby is in the very first stages of life.

13 Energy

Does a baby need energy to survive in the first trimester? Boy, does it ever. And it zaps that energy from its mother. A newly pregnant woman can attest to that because she can barely get through the day thanks to her tiny tot. She may need a nap every day, or she has to go to bed not long after getting home from work. All of her extra energy during that first trimester goes to the baby, which needs a lot to survive and to grow.

During the first trimester, doctors encourage moms to start to add some calories into her diet, although the baby takes it for himself and survives off fat storage if he has to in the first few moms, when some women are saddled by morning sickness and unable to keep her food down. In the second trimester, the mom-to-be needs about 300 extra calories per day, while in the third trimester she needs about 500 additional calories to help the baby put on weight.

The energy that it takes to form a human can be more than your daily cardio workout. The baby uses up that extra energy quicky, and leaves many women exhausted but excited.

12 Have A Heart

John Krasinski (left) stars as Burt and Maya Rudolph (right) stars as Verona in Sam MendesÕ AWAY WE GO, a Focus Features release. Photo: Franois Duhamel

It doesn't take long before a baby's heartbeat begins. In fact, the rhythm starts before the heart is fully formed, and maybe even before a woman can tell if she is pregnant.

The baby's first blood vessel appears at 4 weeks, which is actually only two weeks after conception. That one long tube is the earliest form of the heart, and it begins to beat and push blood through the body by week 5. The heart tube starts to twist and divide and that is how it forms the valves and chambers that make up the completed heart muscle.

It's nothing short of amazing how the muscle takes shape and begins to do just weeks after the egg and sperm meet and the fetus begins to form. The heartbeat is a confirmation that the pregnancy is moving forward and that there is a genuine little baby living in the womb.

11 The Beat Goes On

As we mentioned before, the heartbeat is a sign that the baby is alive, and doctors can pick up the indicator very early into a pregnancy. Many moms-to-be rush to the doctor as soon as their pregnancy test shows the pink line because they want to confirm it through an ultrasound that can detect the heart rate.

The beat of the baby's heart can help doctor's determine how far along in gestation she is and whether or not there are any problems. At 6 weeks, the beat will be slower, about 80 beats a minute, but it will rise quickly and peak at about 170 beats per minute by week 9 or 10. Then the speed will go down a bit and average 120-140 beats a minute. (For comparison, the average adult's resting heart rate is closer to 80 beats per minute.)

Later on in pregnancy a doctor can use a Doppler or even a stethoscope on mama's belly to hear the beat, but at first, he may need to perform a vaginal ultrasound to get closer to the beat and pick up the sound.

10 Fitbit Clue

By the way, the baby's heartbeat is so strong that sometimes you don't need a doctor to help you hear it. In some viral sensations, we have learned that wearable technologies can pick up heartbeats from babies even before mom has performed a pregnancy test.

The Fitbit and other fitness trackers are often worn on the wrist and they monitor the person's heart rate through the artery. Sometimes, though, it can pick up the rapid fluttering of a tiny little one showing signs of life. The Fitbit clue is another miracle that proves there is a little living thing inside a woman and while it is still small and may not have given any other outward signs, like morning sickness, it is making its presence known.

That sign of life can be unexpected but pretty amazing, as a woman wonders why all of sudden she is burning a lot more calories than she ever imagined — thanks to the little guy or girl snacking on them in her womb.

9 Reproductive System

Egg chives and black plate look like sperm competition Spermatozoons floating to ovule

As we mentioned before, one characteristic of a living thing is the ability to reproduce. And while babies can't reproduce even after they are born until they reach puberty, the reproductive system takes shape in the first trimester.

The baby's sex is determined at conception. It's based on whether the sperm contains the X chromosome or Y chromosome, as the egg will always contain an X chromosome. Then, the reproductive system starts to form around week 9, when the gonads begin to form. It will be several weeks until the sex organs are apparent in an ultrasound, but the formation begins during the first trimester.

It's usually the second trimester when moms and dads learn if they are expecting a boy or a girl, but the formation is done by then. That stage of development is another sign of life that happens in the first trimester.

8 Baby Brain

Young mother holding her little cute baby

Just 16 days after a baby is conceived, it's nervous system starts to form. It starts with a neural plate, which grows and folds and folds and folds, and then it forms a tube. That tube closes at about week 6 or 7, although one of the most common types of birth defects happens when the tube doesn't close properly.

That tube becomes the baby's spinal cord. One end forms into the brain and the other end is the base of the spine, and all of nerves are connected to the points in between. A good portion of the cells that are multiplying to form the baby become neurons that build your baby's senses and allow for movements and reactions and reflexes.

It takes a while for the brain to grow and develop. In fact, a person's brain isn't fully developed until they are in their 20s. But the beginnings happen in that amazing first trimester, when baby's life is beginning.

7 Response

That leads us back to the characteristics of a living thing, as the baby's nervous system allows him to respond to stimuli. The neurons in place allow him to move his still developing arms and legs, and it also sets him up for his first reflex, which is curling into the fetal position.

Newborns have nine reflexes that help them survive the first few weeks or months outside the womb. Rooting allows them to find their mother's nipple and latch on. The righting reflex allows most newborns to get themselves out from under a blanket, although some wonder if the absense of the reflex is what leads to SIDS. There's the startle reflex and the tonic reflex, and the baby will automatically withdraw from anything heading toward it quickly, even if it is mom going in for a kiss. The baby will automatically thrust its tongue toward anything going into its mouth, which probably protects it from choking. And we're not sure why, but a newborn will even take steps when put upright on his feet .

All of these reflexes start with the neuron development in the first trimester, and they will guarantee a baby's response to stimuli right off the bat.

6 Deep Breath

A living thing can breath, and while a fetus does not yet have exposure to air when it's in the womb, the beginnings of that part of life start early in the pregnancy.

The lungs start to form at 8 weeks, although the maturation process goes on for seven more months. The baby will start to practice breathing in the second trimester, although it will be amniotic fluid that goes in and out of the lungs. And that fluid has to come out during the first few lungfuls of air after the baby is born.

The lungs are the last organ to fully develop, and that means that some premature babies struggle with their first breaths. But those lungs have taken shape and begun their work during the first trimester, and they are another sign of how alive your baby is during those first three months.

5 Sweet Treats

During its time in the uterus, a baby gets its nutrients through the placenta, but the foundation for digestion begins very early on in development. Even when its just a big mass of cells the cells begin to form three years, and the innermost one, called the endoderm, becomes the digestive system (the liver and the lungs are in there too).

At about 8 weeks gestation, things start to form into a big long tube that eventually folds up and shapes into the parts of the system, from the esophagus to the intestines and then out through the anus. The kidneys are helping to form the urinary system, and a baby actually forms three different sets of them during the first trimester as they do their job of removing waste.

The stomach is up and running by week 10, and it producing enzymes and juices for digestion, although during the pregnancy the amniotic fluid will cycle through the system. After the birth, it'll be all ready for action, although it is still a bit immature, which causes spit up for a few months. Yet the humble beginnings come in that amazing first trimester when all the signs of life start to kick in.

4 The Sad Part

Sadly, one of the signs of how alive your baby is during the first trimester is that it can die. Life can end at any stage, but when it comes to babies, the first trimester is the most vulnerable time. It is the period when most miscarriages come because of all the developmental milestones that have to come together just perfectly in such a short period of time.

Some parents never get to hear the sweet sound of their baby's heartbeat because it is gone as quick as it starts. Some here it once but doctors can't find it the next time around. The fetus can stop growing and those preparations for respiration and digestion can be all for naught.

In the first trimester, when those signs of life are all internal, many women don't even know if they have miscarried the fetus until they learn about it from the doctor. It's so tragic when a life is cut short, and we hope that you never have to experience that for your family.

3 Face Time

Within a matter of weeks, the baby isn't just a mass of cells (although we note that she is a mass of cells because that is one of the characteristics of living things). At the beginning of the first trimester, she may look a little strange, but by the end, she has eyes, nose, and a mouth. Those sweet features are determined by the baby's unique DNA, which is a mixture of mom's and dad's.

Whether the baby will have her grandfather's nose or her favorite aunt's dimples is determined early, and some of those will even be distinguishable on an ultrasound. The eyelids form this early, although they will soon fuse shut to protect those precious baby blues until closer to the time when the baby will be born.

By the end of the first trimester, the baby's voice box will also be formed, so those cries can start right away. She may not be able to show you yet, but your baby is ready to show you just how alive she is with that first cry.

2 Fingerprints

One of the most distinguishing features on a person is his fingerprints. In fact, that is how people are identified for crimes because no two fingerprints are exactly alike. And those fingerprints get started in the womb. It's pretty amazing to know that a ball of cells grows arms and legs and then fingers and toes all within a few weeks.

Before the end of the first trimester, he even has fingernails and toenails. And the beginning of the fingerprints take shape. Scientists believe that the ridges and swirls on the pads of our fingers are determined by what goes on in the womb. It's the way that the baby moves her hands through the amniotic fluid and the layers of skin that form that create the unique shape. And all that starts before the first three months are over.

It's another crazy way that a baby grows and develops into a unique human being in that first amazing trimester.

1 Making Senses

While a baby may be inside his mother's womb, he is a different, unique soul, and that can be evident already in the first trimester. It takes a while to develop all of a baby's senses, but those neurons we mentioned before are in lace, and they are doing the job that they for which they are intended intended.

Baby could go ahead and start discovering his favorite things in the first trimester, and while he doesn't quite get a taste yet, in the very first trimester, he can smell what his mom eats. If she has a hankering for garlic, he might start to love it. Something sweet like strawberries could also make an impression.

Research has proven that a newborn can tell when his mother comes into a dark room just by her scent, so that bond is starting early, even before the baby is 4 inches tall.

So many unique and wonderful characteristics come to your baby in the very beginning of her gestation. She is alive and growing and will soon be big enough to let everyone know it.

Sources: Biology Online, What to Expect, Baby Center, Parenting

More in WOW!