What To Expect In The First Trimester – The First 12 Weeks

When you see those two little blue lines appear on the pregnancy test, your mind starts racing, your body goes numb, and you slowly begin to roll through every emotion. How do I know this? Because I’ve been there.

I remember when I first found out I was pregnant, I was home on my lunch break with my husband. I was a day late for my expected period, and we just thought, ah what the heck, let’s just take a test for fun and see.

Well, to our surprise, the test showed positive, and we were in such disbelief, we took three more tests later that evening, just to be sure. I even took a test in a bathroom at WalMart.

When the reality set in, I remember feeling a rush of excitement, followed by a feeling of overwhelming fear, then a burst of gratitude, followed by the shocking responsibility and realization that I had a tiny little human, the size of a poppy seed, growing inside of me at that very moment.

I’m not kidding when I say I felt every emotion, and that it’s completely normal. In this post, I will break down everything you need to know about the first trimester. From body changes to hormones and emotions, even baby’s growth, you name it, I’ll cover it. Keep reading to find out what to expect in the first trimester.

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First Trimester Fear

Okay, I know this isn’t a pleasant topic, but it’s real. And I know I am not alone when I say the first trimester was by far the most stressful. This trimester can be worrisome for many reasons, no matter how many pregnancies you’ve been through.

The good news is, the first trimester is defined as the first 12 weeks of pregnancy, and depending on when you test positive, you’re most likely already 4 weeks pregnant because it’s calculated off the day of your last menstrual period.

The reason I say the first trimester is the most stressful is because a whole new world has opened up to you. Ever heard the term ‘ignorance is bliss’? Well in my case it had never been truer – I had no idea what to expect when I first became pregnant.

Until you experience pregnancy for yourself, you can never fully understand all the fears and stresses that come with it. That being said, the greatest fear that is most common among almost every pregnant woman is:

Miscarriage – Before I found out I was pregnant, I never understood the worry or fear of losing an unborn child. Having never experienced it firsthand, I still can’t say I fully understand it. But I can say that the fear became very real the moment I learned I was pregnant.

The first trimester is commonly known for miscarriages, which is why many women choose to keep their pregnancy a secret until they reach the second trimester. But don’t let this scare you. There are so many studies and statistics that go into determining this, that when broken down may not even apply to you.

Overcoming Fears Of Miscarriage

To overcome my fears of miscarriage I read up on statistics that worked against my fears. Such as:

• Most miscarriages happen within the first 4 weeks before you even test positive
• The chances of a miscarriage drop significantly after the doctor finds a heartbeat, which can happen as early as 6 weeks (but know that the first appointment is typically set for 9-11 weeks)
• Smoking is a leading cause of miscarriage, I knew that no one around me, and I myself did not smoke, which bettered my chances of keeping the pregnancy.
• I was young and healthy and in good shape, which also lowered the risk of miscarriage

Those are only a few of the statistics that are out there when calculating the risk of miscarriage. These exact statistics may or may not help you. All I’m suggesting is to find statistics to work against your fears. Don’t read the bad news and overwhelm yourself.

Another thing to note is that if a miscarriage does happen, you need to know that everything happens for a reason, and you are not to blame. In most cases of miscarriage, something was genetically wrong with the fetus, making it impossible to sustain life.

I know it’s easier said than done, but try to focus on the positive and ease your mind of miscarriage by understanding the statistics and being informed.

Body Changes & Side Effects

As far as side effects and symptoms go, the first trimester was by far the strangest for me. This was because I didn’t have the big belly or anything physically signifying that I was pregnant. I did, however, have a lot of internal changes that resulted in side effects and outwardly showing symptoms.

I found that most of the side effects and symptoms of the first trimester were pretty similar to the early signs of pregnancy, which you can read more about here.

Gas – Glorious and ladylike isn’t it? I remember a few days before I got the positive pregnancy test, I was so gassy! It seemed to come out of nowhere, and it couldn’t be explained. I knew my diet hadn’t changed but my stomach was very rumbly. This is due to hormonal changes that can cause disturbances in your digestive tract.

Bloating – Along with gas, bloating is another pleasant symptom of pregnancy in the first trimester.

Fatigue – Oh boy was this symptom real for me! There is nothing like pregnancy fatigue. Up until being pregnant, I had never felt exhaustion quite as extreme. But, if you think about it, it makes sense. My body was growing a human for crying out loud! I remember that for a period of time during my first trimester, I would go to bed at 7 or 8 pm every night (I was a real party animal haha) and I would even take a nap in the afternoons on my lunch break!

Increased Urination – Have you noticed, you’ve been taking more trips to the ladies room recently? Well, that’s because of the increase in blood flow to your kidneys, causing your bladder to fill up more quickly than it did before pregnancy. This symptom surprised me because I thought frequent urinating only happened later in pregnancy due to the baby’s head resting on the bladder.

Constipation – The side effects of pregnancy are just lovely aren’t they? Good thing those tiny humans are worth it! Yes, in the first trimester, you will notice a change in your bathroom schedule. This is due to the hormone progesterone. It causes the muscles in your digestive tract to relax and therefore slow down the digestion process, resulting in constipation.

Food Aversions – This one hit me hard, and it goes hand-in-hand with the “nausea” symptom of pregnancy. I remember one night my

husband decided to make burgers for dinner. The moment the smell filled my nostrils, I thought I was going to die from the wave of nausea that followed. Researchers have yet to find the reason behind food aversions, but they are real and they will hit you like a ton of bricks. The good news is, these food aversions don’t last. Now that I’m not pregnant I love me a good burger!

Nausea & Vomiting – Also known as morning sickness, this is probably the most well-known symptom that comes to mind when you think of pregnancy. This is because 90% of women experience nausea and/or vomiting in the first trimester. I was lucky enough to be part of the 10% who never experienced this symptom. Well, I never threw up that is, I did, however, experience nausea.

Light-headedness – It is common to feel a little light-headed during the first trimester and this is due to increased blood flow. Just be sure to listen to your body and to take it easy and get plenty of rest – while exercise is okay, and even encouraged, don’t over-exert your body.

Baby’s Growth In The First Trimester

It’s clear to see that during the first trimester your body undergoes a lot of changes, but most of them can’t be seen from the outside. A lot of the changes during this time are happening inside.

Although you can’t see it, the fetus is growing at a rapid rate. Within these short 12 weeks, the baby develops from the size of a poppy seed to the size of a lime! That is incredible.

Like I said, when I was in my first trimester, it was a confusing time, because I didn’t necessarily “feel” pregnant. I didn’t have a big belly or any of the aches and pains, and I didn’t even experience the infamous morning sickness. So when I found out just how rapidly the baby was growing inside of me I was blown away.

Weeks 1-4: As I mentioned earlier, most women don’t find out they are pregnant until at least 4 weeks. That’s because during this time the sperm and the egg have just attached to form what is called an embryo which will soon come to form the baby. During these 4 weeks, the embryo attaches to the uterine wall and gets to work splitting and multiplying to begin the forming of what will be your new little baby! By the end of these 4 weeks, your baby is the size of a poppy seed.

Weeks 5-7: During week 5, the baby resembles a tadpole, seeing as it doesn’t have fully formed limbs yet. Between weeks 5 and 7 the circulatory system is developed and the tiny heart begins to beat. During week 6 the face is beginning to form, and the eyes, ears, and mouth make an appearance. By the end of week 7, the baby is the size of a lentil.

 

Week 8: During this week, a big growth spurt takes place, the baby doubles in size! It can also move around now, although you most likely won’t feel it, because it’s still too small. The fetus has now begun to lose the tadpole-like appearance and has started to form the beginnings of limbs. Neural development is ramping up and breathing tubes have formed that will soon become the baby’s lungs. By the end of week 8, your baby is the size of a kidney bean.

Weeks 9-11: During these weeks, the baby completely loses it’s tadpole-like tail and has fully formed limbs. By week 10, the baby now has skin, however, it’s still translucent, and the little details are almost fully formed, such as earlobes and fingernails. By week 11, the baby’s diaphragm is developing, meaning your baby can now get the hiccups, however, you most likely won’t feel those just yet. By the end of week 11, your baby is the size of a fig.
Week 12: This is the last week of the first trimester, and your baby is now fully formed in terms of appearance. Everything is in place and it is now looking like an extremely tiny human. Your baby’s reflexes are beginning to kick in at this point, meaning they can feel when you poke or touch your belly. By the end of week 12, your baby is now the size of a lime.
It never fails to amaze me just how incredible the human body is. The formation of life is completely miraculous. It’s awe-inspiring to see just how much growth takes place in such a short period of time.

Once you’ve hit the 13-week mark, you are sailing off into the sunset into the second trimester, which was my personal favorite trimester of pregnancy.

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No More Secrets!

Upon completion of the first trimester, many women find that they are greeted with a sense of relief. The morning sickness and nausea dissipate the unpleasant side effects like fatigue and bloating fade. And best of all, the chances of miscarriage drop dramatically.

Another attribute of the second trimester that many expecting women and couples look forward to is the announcement of their good news! Of course, it’s up to you when you decide to disclose this information with family and friends, however, many couples announce at this time, because there is a very high chance of a continued pregnancy once the first trimester has ended.

Now that you know what to expect in the first trimester, you can get through it and look forward to completing it and moving onto the next.

The end of the first trimester symbolizes triumph for most couples and brings a sense of peace. If you’re like me, you can rest easy and finally get excited about your little one! And believe me when I say the second trimester is much better than the first.

I hope you found this helpful! If you are a new or expecting momma, I would love to hear from you! If you have any questions, comments, or experiences to add, please feel free to leave them in the comments below.

XOXO