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What To Expect During The First Trimester

From this stage onwards, I will break down the pregnancy process and stages to cover every little bit of change that occurs in your body and the various development stages your child will go through, after which I will discuss how to handle the bodily changes.

But before we can actually get to the pregnancy weeks, perhaps you have been wondering what the 38-42 weeks of pregnancy mean.

  • When do they start counting?
  • Is it from the date of conception or from the day of missing your periods?

To answer this, let’s start with pregnancy mathematics 101:

Pregnancy Mathematics 101

The pregnancy results came out positive; congratulations! But just before you can celebrate, I know the reality of the pink line will start settling in.

So the first thing that you probably might want to jump to do is to reach for the calendar to put a big circle on your due date.

Well, then it dawns on you; are you counting from the day of the result or from when you might have conceived?

You have heard that it is 38-42 weeks but from when?

You probably have known your pregnancy for less than 10 minutes and are already confused as to when the baby is coming.

Well, for starters, health practitioners agree that pregnancy takes an average of 40 weeks even if just about 5% of the babies are actually born within that period.

You will still be okay if you deliver in the range of 38 to 42 weeks. So 38 weeks is not exactly early and 42 weeks is not late.

But what is the starting point? Well, it does not start from the day you conceived.

Instead, it starts from the first day of your last menstrual period. This is something that doctors have come to a consensus on given that it is a more objective and probably accurate way of determining when you can expect to deliver.

This is so because while you might know when you started bleeding, you really cannot be sure on when you started ovulating. And besides ovulation, you cannot be certain when you actually conceived.

Keep in mind that the fertilization process can take up to 24 hours or even longer after your ovulation occurs.

When this is coupled with the fact that sperm can hang in there with your body for up to 3 days after intercourse, you really cannot have absolute certainty when the sperm got to the egg and actually fertilized it.

As such, start counting your due date from the first day of your last menstrual period; even if the baby is technically up to 2 weeks younger.

So in essence, you will have reached your 38 weeks of the gestational period when you are in your 40th week.

Instead of wasting too much time counting weeks, here is a calculator to make everything easy for you. But if you have some irregular periods, talk to your doctor about it to get a clear estimate of your due date.

Now that you are aware of how to calculate your due date, let’s start learning what happens in the different weeks.

Week 1 & 2

The changes that occur between week one and the week two aren’t much. That’s why I have to combine them together to avoid repetition.

In the first week, your body will not undergo many changes before your body has yet to start producing pregnancy hormones.

This is the earliest stage of your pregnancy and surprisingly, at this stage, your body is all set up for ovulation and getting ready for fertilization.

The ovulation time is very important when you want to conceive. Ovulation usually takes place when a mature egg is released from the ovary and then pushed down the fallopian tube for fertilization.

You already know that fertilization occurs when a sperm meets the egg.

Then at this time, the uterus lining thickens preparing for the fertilized egg. Ifconception does not take place, the lining sheds during the process of menstruation.

Week 3

Fertilization probably occurs in the third week; it is during this period that the sperm meets the egg; the baby at this stage is made up of a group/ball of cells with several hundred cells that multiply rapidly referred to as a blastocyst.

The blastocyst then starts a 6-day journey from the fallopian tube towards the uterus where it will ultimately attach itself to the uterus lining.

The part of the blastocyst that will grow into a placenta has probably started producing HCG (human chorionic gonadotropin), the pregnancy hormone, which signals the ovaries to stop releasing more eggs and then triggers the production of progesterone and estrogen.

The role of these two hormones is to ensure the uterus does not shed its lining and its tiny passenger and help in stimulating the growth ofthe placenta.

On the other hand, the amniotic fluid has started collecting around the blastocyst within the cavity, which will ultimately become the amniotic sac. The purpose of the fluid is to cushion the baby as it grows in the coming weeks and months.

Additionally, the blastocyst is receiving oxygen and nutrients and discarding waste with its pretty primitive circulation system, which is comprised of microscopic tunnels, which connect the developing baby to the blood vessels within your uterine wall.

At this time, your placenta isn’t developed enough to do its job until the end ofthe following week.

The sex ofthe baby is already determined at this time. The pregnancy hormones also start to build up at this stage; although you will not experience much signs from your body that you’re pregnant on the third week.

The baby’s DNA is already determined

with 46 chromosomes i.e. 23 from you and 23 from the father. You, the mother provides the X chromosome while the father provides the X or Y chromosomes.

So if the baby got X chromosomes from the father, it will be a girl (XX) and ifit was Y, it will be a boy (XY).

Week 4

At week 4, the blastocyst has probably attached to the uterus lining and is now an embryo. The embryo then splits into 3 sections.

One section becomes the nervous system and the brain then starts developing the necessary neural pathways (tubes).

Then another section forms into the heart and the circulatory system and finally, another part becomes the lungs and the intestines, which start developing rapidly.

You may start to experience minor symptoms ofpregnancy at this stage, and it is advisable to continue taking folic acid at this stage to help develop your baby’s nervous system.

At four weeks, your baby is just a tiny 3mm long, no bigger than a poppy seed.

Week 5

At the fifth week, your baby should have added an additional 2mm to his or her length making him or her 5mm long. At this week, the baby’s brain, spine and heart continue developing rapidly and soon the heart will actually start beating, so if you do a test scan this week, you will probably see some flickering on the monitor.

At this stage, the heart is just a single chamber organ. The baby’s head also shows signs of development especially with the development of the neural tube i.e. this is the start of the connection between your brain and the spinal cord.

The neural tube will help in regulating the baby’s vital functions such as blood supply and the heart rate. The baby probably looks more like a tadpole this week but the limbs will start taking shape.

It is also at this stage that the test machines and stripes can show a positive sign when you undergo a pregnancy test because the Human Chorionic Gonadotropin (HCG), which is the pregnancy hormone, is at an all-high level at this stage.

At this stage, you may start feeling dizzy at times and easily tired, for which you should try to get plenty of rest and eat a healthy diet with plenty of fruits and vegetables.

Week 6

The baby’s heart is probably the size of a poppy seed by now. But even with its tiny size, it has become fully developed into a four-chambered organ.

Remember that prior to now, I mentioned that the baby had developed a heart, but the heart was just a single chambered organ.

Now, the heart is fully developed and beats at a rate of 160 beats per minute, which is more than double the number of times a human being’s heart beats; an ultrasound scan can detect this.

Also, it is in the sixth week that your baby’s facial features begin to develop; that means that your baby’s nose, mouth and eyes start to take form in the sixth week. An ultrasound scan will usually show some dark spots where the nostrils and the eyes form while the ears will show as small depressions.

The baby’s body is also covered by a thin layer of see-through skin and the different body organs like the liver, the lungs and the kidneys are now in their rightful place although they still need to develop greatly.

Week 7

Before the seventh week, the baby is still in the form of an embryo, but in this week, the embryo will gradually start taking the form of a small human being.

The baby’s arms and legs also develop at this period, and the baby is estimated to be around 1cm long (no bigger than a little bean) at this stage with a beating heart, some emerging leg and arm buds.

Apart from the heart, another major organ that gets to develop at this stage is the kidney; well, the baby has already had 2 other sets of kidneys by this time but this week, this is the final set of kidneys that the baby will live with for his or her entire life.

In the coming few weeks, the kidneys will start producing urine to form part of the amniotic fluid. For you as the mom, the increase in length and rapid development of your baby will exert pressure on your kidneys, thereby giving rise to frequent urination.

Week 8

You are now 2 months into the pregnancy. In the eighth week, your baby is estimated to have grown to 2cm long and growing at about 1 millimeter per day.

The baby will start producing urine, which is included in the amniotic fluid; your baby is estimated to start producing 2 teaspoons of amniotic fluid every week.

Your baby is now officially referred to as a fetus (meaning offspring); it is no longer an embryo although it still feeds from the yolk sack, which should be changing to the placenta in the coming weeks.

In the weeks to come, the placenta will grow the chorionic villi, which usually help in attaching the placenta to the womb wall where the baby can feed from it. The fetus’ tiny fingers and the toes are now nicely formed although they are sort of webbed as they continue growing for the weeks to come.

The heart still beats at 160 beats per minute, the lungs continue developing (at this stage, the baby develops a breathing tube extending from the lungs to the throat while the brain nerve cells start branching out and connecting in a bid to form what is some sort of primitive neural pathways).

The baby still has a paper-thin skin, which is somewhat transparent with an embryonic look while the color pigmentation on the eyes starts forming although the eyes won’t open until around week 26; the eyelids cover the eyes completely at this time.

For you the mother, your womb should have grown at least twice its normal size, although your bump shouldn’t be that noticeable.

Morning sickness is likely to set in, and for some moms they will start feeling some movement in their womb from this period on.

Week 9

The fetus is about the size of a large bean or olive i.e. about an inch long on its 9th week. This is the third month; your baby’s muscles and nerves begin to fall in place while his or her heartbeats become stronger.

The baby also starts developing its nerves, muscles and other organs although you still won’t be able to feel it.

Additionally, at this stage, the baby’s heartbeat is strong enough to be picked up by a Doppler although this isn’t always possible; it depends on where the baby is in the uterus.

Also, the eyelids and the ears are developing rapidly. For you the mom, you will notice an expansion in your waistline. Also, your breasts become heavier and sore, and you are more likely to become very tired easily this week.

Week 10

Your little one is about 3.8cm long by now. Your baby starts to develop bones, cartilages, some body tissues, and nails on the fingers and toes.

The jawbone starts to set this week and the heart is fully formed, beating at speeds of up to 2-3 times your heart rate. The baby’s skin starts developing some peachy fuzzy hair.

The baby also has their spinal nerves, which have started developing from the spinal cord and if the baby is a boy, he will start producing testosterone this week.

Amazingly, the baby already has its future milk teeth somewhere in the jawbone but they won’t break through the gums until at least 6 months after they are born. Your baby has the ability to swallow fluids at this stage and can produce digestive juice.

For you the mother, you will likely experience some movements in you, as the baby starts to kick. Your uterus has also grown in size to the size of a grapefruit by now; you can feel it right above the middle of your pubic bone.

Also, you are likely going to experience constant constipation since your gut will become slow as a result ofthe multiple changes going on in your body at this time.

Week 11

At the 11th week, your baby starts to take the form of a human being, and should be able to flex (open and close) his hands; they already have fingernails.

It is also at this stage that your baby’s sex gets to develop; for a female, the ovaries start to form and for male the testes begins to form, although it may not be detected by the ultrasound machine at this stage. All the bones in your baby’s face should be present at this stage.

Also the tongue and palate are in their place in the mouth. The baby’s head is very big at this time and it is estimated to be as big as one-third of the baby’s whole body while the baby’s length should be at 4cm now.

However, the body starts straightening and starts becoming a lot more proportionate. The ears have also migrated closer to their final position.

Additionally, the nasal passages start opening at the tip of the nose while the hair follicles start forming on the crown of their head.

For you, the morning sickness should have eased off a little bit now, while the dreaded stretch marks will start appearing in full force on your body.

And although you might not be able to feel everything that’s taking place in your womb, the baby does lots of stretching, wriggling and somersaults and may even have a few hiccups as their diaphragm starts forming.

Week 12

At the 12th week, the baby is about 6cm long and can bend his elbows and wrists. The baby can also wiggle, clench eye muscles, curl fingers and toes, and make sucking movements using their mouth.

Although you might not exactly feel your baby moving, if you poke your stomach a little, the baby will wiggle. Also, it will start practicing how to suck and breathe on its own while the intestines start to develop and the kidney will start testing the process of excreting urine.

The baby’s skeleton at this time is entirely made of cartilage (the kind you find on your ears and nose) although it will start hardening in the coming weeks to form the bones.

At this stage, the baby’s skeleton has over 300 parts of cartilage and bone but this will narrow down to 206 when the baby is an adult since the bones fuse together to produce stronger and larger bones.

You can go for a scan this week.

Besides the skeleton, the baby’s intestines and other organs are changing rapidly this week. The intestines grow to form the umbilical cord.

For you, you should start feeling a little bit stronger these days and very emotional since your hormones are acting up.

While some of the explanations above seem all nice and interesting, the reality is that these come with more complications (or should I say, challenges) with regards to the various changes in your body that you have to figure out how to deal with.

Let’s look at some few challenges that you may face during this period and how you can deal with them.

Tips To Make It Through The First Trimester

These are some challenges you will likely face during your first trimester; most of them will be as a result ofhormonal changes in your body and each challenge comes with a tip or two on how to handle it.

  • Sore Breasts

    During the first trimester, your breasts become heavier and sore. This is caused by hormonal changes.

    You can wear a bra that is a size bigger than your normal size.

  • Vaginal Discharge

    This is also known as leukorrhea and is milky in color. You can use a panty liner to hold off the discharge from staining your panties.

    You are advised not to use a tampon to avoid infection.

  • Fatigue

    Your body is working extra hard during this period in the development ofyour baby and production of pregnancy hormones so you will most likely feel fatigue most times.

    You need to take as much rest as possible.

  • Food Cravings

    Although you are allowed some extra calories in this trimester, you shouldn’t allow the craving for food to reign over you, to avoid adding excessive weight. You can satisfy the cravings occasionally but still remember to maintain portion control while you are at it.

    In other words, don’t start eating for two yet. Make sure you report an unusual craving for dust and clay to your doctor as you may have pica.

    While pica is rare, it is not unheard of and it can cause you to have unusual cravings for non-food items such as dust and clay.

    Indulging in these cravings can be harmful to your baby so see your doctor immediately to have your iron levels checked and do not give in to the cravings.

  • Frequent Urination

    The uterus is adding pressure on your bladder, which is the cause of your frequent urination. The only solution here is to try to visit a restroom as soon as you have the urge to urinate to avoid soiling yourself.

  • Morning Sickness

    You can reduce the morning sickness and vomiting by eating high protein snacks like fish (but avoid shark, swordfish and marlin) and chestnuts.

    Crackers also help to reduce the urge to vomit. Also, you can lie down on your tummy to reduce nausea.

  • Nutrition

    Your baby is undergoing its first stages of development and is still very tender. Ensure your meals contain more ofproteins and vegetables to provide enough nutrients for your baby.

  • Exercise

    With the morning sickness and nausea, you may not be in the best mood to exercise at this period; just try going for walks around your neighborhood, and use the stairs instead of the elevator.

    Now that you are aware of what happens in the first trimester and how to deal with the changes/challenges that come with the first trimester, let’s now move on to the next trimester.