Everything You Need To Know About First Trimester Growth During Pregnancy

Are you newly pregnant or thinking about trying to conceive? This post contains everything you need to know about first trimester growth and what to expect!

Becoming pregnant is one of the most exciting phases of life. It is such an indescribable feeling to grow a new little life, feel his or her kicks, and nine months later finally meet that sweet face. But like anything in life, pregnancy does not come without its challenges and worries too.

In this post, you are going to learn everything you need to know about first trimester growth, week by week pregnancy symptoms and tons of pregnancy tips! You can even download a hospital bag checklist for the entire family if you want to be extra prepared.

This post is all about everything you need to know about first trimester growth during pregnancy.

First Trimester Growth

The first trimester of pregnancy lasts for twelve weeks – but you might not even know you are pregnant those first few weeks before your missed period.

During the first trimester, you will not look noticeably pregnant yet but you will probably feel it. Between the surge of pregnancy hormones prepping your body for baby and the nausea, sometimes pregnancy can start off a little frustrating.

But remember the discomforts are temporary and it is usually smoother sailing as you enter the second trimester of pregnancy.

Are you unsure what week you are in pregnancy? Click here to calculate your due date.

Mom’s First Trimester Growth

You will experience many first trimester body changes during this time such as nausea, mood swings, food aversion and fatigue as well as the potential for many others. This is normal and part of the joys of first trimester growth and development.

Common First Trimester Body Changes:

Exhaustion
Nausea
Headaches
Mood swings
Bloating/Cramping
Breast soreness
Frequent urination
Food aversions
Heartburn
Stuffy nose
Vivid dreams

Now let’s talk more in detail about a few of these in more detail.

1. Nausea

It is extremely common to experience mild nausea, mostly in the form of morning sickness, during the first trimester. It is also normal for pregnant women to experience nausea randomly during the day or even consistently at night though.

You can expect morning sickness to start as early as six weeks and will start to ease by twelve or fourteen weeks when you are into the second trimester. But trust me, I know it can feel neverending when you are in the middle of it.

If you are concerned about your nausea during pregnancy or are experiencing extreme nausea, it is always a good idea to talk to your doctor.

Hyperemesis gravidarum is a condition that comes with severe nausea and vomiting during pregnancy that can lead to weight loss and dehydration. You can think of this as an extreme and more intense form of morning sickness.

2. Mood Swings

You can expect to be a big ball of emotions during pregnancy. It sounds dramatic but you can blame your pregnancy hormones for it!

During the first trimester of pregnancy, higher levels of estrogen and progesterone can lead to mood swings. You can be blissfully happy one day and irritability or sad the next. Pregnancy is also a huge life change which contributes to the emotions flowing like they do!

3. Food Aversions

Strong cravings and strong aversions are common during pregnancy and we can thank our changing hormones for that.

The amount of HCG (human chorionic gonadotropin) doubles every few days during the first trimester of pregnancy and peak/level off around week eleven and generally leads to food aversions. Some women experience food aversions for a limited time while others experience them for the entire nine months of pregnancy.

4. Exhaustion

Most women experience exhaustion and fatigue during the first trimester of pregnancy. I think every pregnant woman out there will tell you that exhaustion during the first 12 weeks can be pretty intense but it is 100% normal.

Many women are also dealing with nausea and many of the first trimester body changes listed below too, so it can be challenging getting out of bed and not falling asleep at your desk at 10am.

Pregnancy weight gain is usually only a few pounds but things like nausea can really impact it up or down. My advice is to not worry about the number on the scale. Your doctor will be monitoring you and will make sure you are gaining a healthy amount of weight.

Baby’s First Trimester Growth

Your baby does A LOT of growing during the first twelve weeks of pregnancy. He or she will grow from a single fertilized egg to an embryo to a peach sized bundle of joy who grows organs and limbs. It is really incredible when you think about it.

First Trimester Growth: Month 1

During the first month, the amniotic sac forms around the fertilized egg to help cushion the growing egg during pregnancy. The placenta also develops and is used to transfer nutrients from you to your baby.

Your baby will start to develop dark spots for eyes and his lower face (mouth, jaw and throat) will also take shape. Blood cells take shape, circulation begins and by the end of month one, your baby is about the size of a grain of rice.

First Trimester Growth: Month 2

In the second trimester of pregnancy, your baby continues to grow rapidly! Flaps, that will eventually be ears, grow out of the side of his head along with little buds for arms and legs. Throughout the month, his fingers, toes and eyes will develop too.

As early as two months, your baby’s brain, spinal cord and other neural tissues of the central nervous system are well developed.

Other developments include the digestive tract, sensory organs and bones in replacement of cartilage. Your baby’s skin will also start to develop too.

Your baby is referred to as a fetus by the end of month two.

First Trimester Growth: Month 3

By the end of this month, your baby will be fully formed and will have arms, hands, fingers, feet and toes.

Fingernails, toenails, and teeth are developing at this stage of pregnancy and your baby’s reproductive organs are forming too. Despite this, it is still hard to determine the gender on an ultrasound.

First Trimester To Do’s:

Start taking a prenatal vitamin. You may have started taking a prenatal when trying to conceive, but if not, make sure you pick one up because this is so so important! A prenatal is especially important in the first trimester because it has been shown to reduce the risk of neural tube defects such as spina bifida.
Choose your OBGYN. You have a few different options to choose from including OBGYN or midwife. You will want to confirm what hospital the doctor or midwife has privileges at as this is where you will be delivering your baby.
Book your first OBGYN appointment. You are usually seen around weeks seven to eight of pregnancy. Your doctor will review your medical history, do a full exam and you will have your first ultrasound, although depending on your doctor’s office it could be scheduled on a separate day.
Cut back on caffeine. Now is the time to learn about what foods you should avoid and start cutting back on the caffeine to about 200mg or less per day.

Start researching daycares. Believe it or not, daycare spots can be hard to come by so the earlier you start researching and going on tours, the better. I suggest talking to at least three so you have several to compare. Once you decide on the daycare center or home daycare, give your deposit to hold the spot.
Make a budget. Diapers, wipes, formula and daycare all add up. Making a budget early on in your pregnancy and figuring out the added expenses you need to allow for should take away some of the stress.
Start thinking about baby names. It is never too early to start thinking about baby names! You do not have to make a definite choice during the first trimester but it can be helpful to discuss it with your partner early on so you have plenty of time to find a name that you both love.
Announce your pregnancy. Many women decide to wait to announce their pregnancy until after the first trimester but there is no hard and fast rule about it. Regardless, you will probably want to share the good news with your family before announcing to friends on social media. There are so many cute ideas on Pinterest you can try!
Start buying maternity clothes. Some pregnant women are able to comfortably stay in their pre-pregnancy clothes through the first trimester, but it is common to experience a lot of bloating and discomfort early on. For this reason, it is not a bad idea to pick up a pair of maternity jeans early on. They might be a little big when you first buy them, but you will grow into them in no time!