20 Must Knows About The Third Month Of Pregnancy

Every stage of pregnancy is important — each week has a significant milestone for mom and for baby, and things can seem to change each day. But the third month is a time that stands out among all the rest.

The first trimester is a time of incredible development for the embryo, where the egg grows into a blastocyst and then into different cells and organs that make up the baby. Those first eight weeks are full of excitement, but the next four weeks — the third month-is even bigger.

Between weeks nine through 12, the embryo becomes a fetus, and while there are incredibly important developmental milestones that have to be met, during that time period, many moms start to feel better, and they get to hear the heartbeat. And at the end of that time, it's often time to start spreading the exciting news of the pregnancy among family and friends. There are still six months to go, but getting through the third month is an achievement that is cause for celebration — and for most moms-to-be, the journey becomes a lot smoother after that critical month.

Here are 20 facts about the third month of pregnancy.

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20 Finally Looking Like A Baby

Most of the first trimester of pregnancy, the embryo growing inside of mom doesn't look much like a baby. It starts off as a ball of cells and then it kind of morphs into a tadpole-like thing with a big head, no neck, and a tail. But that changes around week 9.

In the third month of pregnancy, the baby starts for form a neck, and the tail begins to go away. While the head is still bigger, the fetus starts to look like a baby, and the external details start to get filled in. By the end of that month, the baby is pretty recognizable as a tiny human.

19 Hearing Baby's Heartbeat

For most moms-to-be, a first-trimester doctor's appointment is scheduled for the third month, although sometimes it comes as early as week eight. The event is a big one, as mom meets the obstetrician, gives her family history and can even have an ultrasound, although, at that point, it's usually hard to see much more than a sac and a shape that represents the baby.

The most amazing part is when the doctor checks on the baby's heartbeat. The heart starts beating around six weeks, but it takes a couple more weeks to actually be able to detect it. And when that sound comes through, it's not only an amazing sign of life, but it can be a big relief. The possibility of miscarriage goes down dramatically after the heartbeat is detected, so that's a huge highlight of the first-trimester doctor's appointment.

18 The Girls Get Extra Pigment

Pregnancy changes continue to happen to the mom's body in the third month, even though some moms still don't appear to be pregnant at first glance. It might be more obvious for the mom's partner, though, as her girls continue to change in the process.

The chest area is often the first to get bigger for moms-to-be, and it can start as early as conception. That will continue in the third month, but another change can come then too. Many moms get more pigment on the tips, which means that they can look darker and larger. After the birth, the pigment change helps the baby see their target when trying to latch, but at this point, it might seem like another weird symptom.

17 Jeans A Little Too Tight

At the ninth week, most moms-to-be haven't gained much more than a pound or two. They might have even lost weight because of their morning sickness. But their uterus is starting to expand a tiny bit, so during the third month, they might start to experience some tightness in their jeans.

Some women can continue to wear their jeans through the third month and even fourth one, but they might have to use a rubber band to keep the button together. Even though the baby is growing quickly, mom's body is just starting to show any changes on the outside.

16 Boy Or Girl Parts Develop

Moms-to-be are still a couple of months away from their gender reveal, but the parts that show whether or not it is a boy or a girl start to develop in the third month. Of course, the baby's sex is determined at conception, as it is marked in the DNA. But it can take a while before that is obvious.

The external organs begin to develop in the 11th week of development. There are some parts for boys that don't drop on the outside even at birth, so it can take time for it to be obvious if it is a boy or a girl. Some people are having earlier ultrasounds, which can be exciting, but there is a possibility for error since things aren't so obvious at first. In fact, there are times when doctors make a mistake and parents learn at the birth. Week 11 is just the beginning for that.

15 Cute Little Ears

As we mentioned earlier, at the beginning of the third month, the baby doesn't exactly look like a baby. But a lot of the details start to emerge between weeks nine and 12, and that includes some of the details of the face. The babies eyes move into position, and finally, the external parts of the ears take shape.

The baby's face begins to take on its shape in the 12th week. Those sweet little swirls of the ears are just precious, but the most important part is the way that they develop the baby's senses. It'll be a few more months until the baby can hear what is going on outside of the womb, but it all starts in that third month.

14 Elbows And Knees

In the 10th week of pregnancy, baby's little joints form. The embryo's arms and legs have been lengthening for a few weeks, but this is the point when the baby actually gets his elbows and knees.

Joints are important since it would be impossible to crawl, walk or even feed ourselves without them. The body has a number of large and small joints that we don't think much about but we can't do without. So this stage is pretty important, and not just because the baby is forming cute little knees.

13 Less Than Two Inches Tall

The third month of pregnancy is a time of amazing growth, even if it is measured in inches. At week nine, the baby is one inch long, and by the end of the 12th week, he is about two inches long. That is still really tiny, but if you think about the baby has doubled in size in just 28 days.

The third month is the biggest yet, in terms of growth, although, the baby will start to grow even quicker from there. An inch might not seem a lot, but considering what that month means in development, this time in the little one's life is definitely a big one.

12 Baby Bones

All moms want their babies to have strong bones, but that doesn't happen in the first couple of months. That early on, babies just have cartilage, which is the substance that later makes up the joints, around week 11, the baby's bones begin to harden and become the things that we would recognize.

Baby's bones are very important. There are more than 300 bones formed by the baby's birth, so this is an important stage that means a lot for the baby's health. It's another important moment in the third month of pregnancy.

11 Mom's Beautiful Hair

There are some perks to pregnancy, and a few of them show up during the third month. Pregnancy hormones are a big deal in the first trimester, but at the very beginning, that thing that mom notices the most is the morning sickness. It can take a little while, but pretty soon she will see the positive.

In the third month, most moms start to experience the good hair that can come with pregnancy. She gets more luscious locks and even thicker and better fingernails.  By the end of the third month, the morning sickness might get better, but for some, it's all just "good hair, don't care."

10 Teeth Start Out Already

While baby's first bones are just starting to harden, it's amazing to think that during the third month of pregnancy, they are also starting to get their teeth. Of course, most babies don't get teeth until they are four to seven months old, although some are born with a few teeth. Despite that, teeth for all babies begin to form in the 12th week.

Tooth buds are just the beginning. They aren't hard enough to bite and they will be underneath the gums by birth. But it's amazing to think that the chompers are already beginning their formation a good six months before the baby arrives.

9 Baby Moves A Lot

Many moms might imagine their babies in their wombs growing, but not really moving in the third month of pregnancy. First-time moms might not feel the baby move until the 20th week of pregnancy, but the truth is that the baby is moving around in the third month.

The baby is moving his legs and his hands. He has a lot of room in the womb to flip around and explore. Sometimes women can feel the baby moving this early on in the pregnancy, especially if she has gone through pregnancy before. And that is really exciting.

8 Baby's Urinary System Starts Working

Moms know that they will need lots of diapers for after the birth because babies poop and pee a lot. But they may not know that their baby starts emitting waste as early as the third month of pregnancy.

The baby's kidneys are already starting to work, and so is the liver. That means the urinary system is ready to start operating. So as the baby takes in amniotic fluid through his mouth, he also emits his waste in it through the urinary tract. That will go on for about six more months until the birth.

7 DHA And Vitamin D Are Important

Moms should start taking prenatal vitamins before the third month of pregnancy — it's best to begin taking them when you start trying to have a baby and definitely get started when you find out you are pregnant. But in that third month, DHA and Vitamin D are important for the development of the baby.

DHA is important for brain development, so that will be important for the entire pregnancy. But Vitamin D is especially vital in the third month because it is so important for bone formation. As we've mentioned already, the baby's bones harden in the third month, so a little extra vitamin D might help even more.

6 Mommy's Little Lime

It's hard to imagine what is going on with the baby while he is in the womb, so one way that experts have helped out moms is by talking about the baby's size in terms of fruits and vegetables. That can really help in the first few months, so we added it as a special section in this article.

The baby starts out the third month about the size of a grape, but it ends it around the size of a lime. That can be confusing, since limes are many different sizes, so some babies hit that size at 10 weeks. The baby is still pretty small at the end of the third month, as the biggest growth happens in the third trimester.

5 Fingernails and Toenails

We mentioned already that the details come in with the baby in the third month. That means that while their little hands have already formed, this is the time when the tiny little fingernails start to form.

The same is true for the tiny, itty bitty toenails. They might seem small that the baby's birth, but they are even smaller in the third month, just starting to form. To think that they will be growing for six more months is pretty amazing — and it's no wonder that they often need a trim not long after the birth.

4 Second-Time Moms Might Get A Bump

A lot of women don't have much of a baby bump in the third month — some might not have any outward signs until the fifth or even sixth month. That is especially true during a first pregnancy. But there are a few occasions when the bump can come in the third month, including if the mom is having multiples.

For second, third and fourth time moms, the uterus has started out bigger, and the body knows how to expand a little quicker. Their bumps can show up as early as the eighth or ninth week, although it might not be too obvious to others until later on in the third month.

3 Reflexes In The Womb

By the third month, many moms start wondering what's going on in the womb. The baby has most of his organs, although some aren't fully developed, so it's more about the growing and moving than the developing. And the baby is doing a lot in the third month.

At this point, the baby is moving around, and he is practicing a lot of things that he will do after the birth. The baby is already practicing his sucking reflex. It's been documented on ultrasound. The baby might even find his thumb or finger and suck on it, just like they do after the birth. It's amazing to think that life in the womb has some similarities already to what it will be outside of it.

2 Heartbeat Fast And Strong

The baby's heart is one of the first things to start developing. It begins beating just a month after conception, although it continues to take shape throughout the first trimester. At the beginning of the third month, the baby's heart has already divided into four chambers, and the valves are developing.

The amazing thing is that the heartbeat is fast and strong. The heart will beat between 120 and 160 beats per minute, which is a lot faster than mom's heart. Heart defects are the most common birth defect, so it's still possible there could be an issue, so be careful with what you eat and drink.

1 Mom's Hormones Level Out

For the first part of pregnancy, it isn't always a joyous occasion. No matter how excited a woman is to become a mom, she can feel pretty poorly between nausea and the tiredness that happens in the first trimester. All of that happens because the mom's hormones are doubling each day, as the body prepares for pregnancy.

In the third month — usually, toward the end of it — the hormones start to level out. That means that in the 12th week or so, many women start to feel a little more energy and a lot less nauseated. At the end of the third month, moms are in their second trimester, which is usually a little easier than the first one.

References: Ask Dr. Sears, Being The Parent,

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