First Trimester Of Pregnancy Symptoms Come And Go

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First Trimester Of Pregnancy The Ultimate Guide To Your First Tri.

Well first off I’d like to congratulate you on this pregnancy. If you are researching what can be expected from this amazingly crazy, season of life – you are in the right spot. The first trimester of pregnancy is crucial and important and this is going to give you the info you need to tackle it safely.

We are going to go in depth to the first trimester. I want you to be prepared and ready for anything that may be thrown your way in these first few months.

This post may contain affiliate links. For my full disclosure see here.

How Long Does The First Trimester Last?

The first trimester of pregnancy is calculated from your last menstrual cycle to the end of the 13th week of pregnancy.

If you fall anywhere from the first through 12th week of pregnancy you are in the first trimester.

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How To Calculate Your Due Date?

An average pregnancy is 40 weeks long. In order to calculate your due date you must add 280 days (40 weeks) to your last menstrual cycle date.

Your period and ovulation are counted as the first two weeks of pregnancy. That means that if you deliver on your actual due date your baby is 38 weeks of gestation not 40 weeks.

Baby’s Growth During The First Trimester

In the first trimester growth for baby is considered how they are developing in size and anatomy as well as your placenta and expanding uterus.

The First Four Weeks

Implantation has taken place and you may now be having positive pregnancy tests. Normally you can take a pregnancy test 4-5 days before your missed period.

You can also ask your doctor or health care provider to do a blood test by the fourth week to confirm your pregnancy.

Baby is the size of: a poppy seed, around 0.04 inches long.

Mom to be is about a month pregnant and may not be feeling any pregnancy symptoms except a missed period.

Baby’s Growth: 5-6 Weeks

Your baby is now taking shape. As well as your placenta and the amniotic sac which are both still forming in the beginning of week 5. Your baby is also forming major body parts like the heart, brain, muscles and spinal cord.

By the end of the sixth week baby is: about .25 inches long and the size of a sweat pea.

By the end of week 6 expecting moms are about a month and two weeks along.

7-9 Weeks: Baby Development

By the end of week 9 baby is now considered a fetus and no longer an embryo. That means your baby has grown and now weights around .7 ounces and is the size of about .9 inches.

*Baby is moving inside, but is to small to feel any movements on the outside*

babys fetus embryo growth weeks 4-9

Weeks 10-12

Now is the time that most doctors will see an expecting mom. Normally if you call the moment you find out you are pregnant they will give you an appointment to come in around the 10th – 12th week.

When will I be able to hear baby’s heart beat?: By your first appointment you may be able to hear baby’s heart beat. Baby now has all it’s major organs and now just needs time to get everything else going.

By the end of the 12th week baby is the size of: a plum around 2.1 inches long.

Early Pregnancy Symptoms

These first trimester of pregnancy symptoms are the most common, remember each pregnancy is different and some women experience all or a few of these symptoms.

If you are having no pregnancy symptoms and don’t feel pregnant in the first trimester – that is also common.

  • Slight weight gain
  • Nausea
  • Morning Sickness
  • Overly Tired
  • Bloating
  • Tender Breasts
  • Constipation
  • Changes In Libido
  • Smell Aversions
  • Constant Need To Pee
  • Sleeping Problems

Slight Weight Gain

You can expect to gain anywhere from 0-4 pounds in the first trimester of pregnancy. It is also not uncommon if you lose a few pounds in the first trimester due to morning sickness or nausea. Which isn’t much of a concern if it is anywhere from 1-2 pounds that you have lost.


Experiencing nausea in the first few weeks of pregnancy is one of the most common symptoms expecting moms get. If you feel sick to your stomach that you are almost going to barf but you don’t that is considered a part of nausea.

Morning Sickness

The name morning sickness is very misleading. Expecting moms can get sick any time of the day. It is more common in the morning because you have an empty stomach.

Overly Tired

This was my first indicator that I was pregnant before I even took a test. If you are like me a ‘go-go-go’ type of person and you notice that you are so tired by mid-afternoon, it is just a symptom of growing a little human.


Just like when you are due for your period, bloating is very common in the first few weeks of pregnancy.

You can experience slight bloating to full on bloating that doesn’t let you zip up your pants.

Tender Breasts

In the first few weeks you may experience tender breasts. Your breasts are already getting ready to breastfeed from the moments you become pregnant. Not only that but the increased amount of blood that you body is making, is making its way to your breasts making them more sensitive than before.

Tackle every trimester easily even if nausea and fatigue are poking their head in the door. Grab your copy of the Totally Trimester to-do list and easily check items off your pregnancy checklist


When you find out you are pregnant – you may start making changes to your diet this can in turn have consequences on your bowels. Constipation is very common during each trimester of pregnancy because of the hormones and dietary changes.

Changes In Libido

Just like tender breasts, your sex life may be changing during the first few weeks of life. Some pregnant mothers experience an increase in sex drive – due to the increased blood flow to their lady parts.

While others may experience a lack of sex drive due to being overly tired. It takes a lot to make internal organs and eyeballs.

Smell Aversions

It can start very early. Maybe one of the earliest signs and symptoms you are experiencing before even taking a test to confirm. Your heightened smelling nose is ready to smell (even the most unpleasant smells).

Smells you liked before, may now become disgusting. Or things you found smelly may now be comforting. It’s the hormones.

Easily remember what you need to get done each trimester (even when nausea and fatigue poke their head in the door). Use my Totally Trimester To Do List – and see how easy it is to check things off your list.

Constant Need To Pee

Your body is shifting all its organs around to make room for your growing placenta and baby. This constant need to pee – let’s up a little durign the second trimester but picks up steam when baby is larger and sitting above your bladder in the third trimester.

Sleep Problems

If you are having sleep issues in the first trimester like slight insomnia, constant wakings and cold sweats it is all part of the hormones going through your body.

You can grab a pregnancy pillow to help sleep easier and give your back some much needed rest when you get further along.

Symptoms That Raise Red Flags During The First Trimester

I am not a licensed doctor but I have had my fair share of miscarriages as well as a healthy pregnancy and I want to let you know if you experience any of these symptoms you should go to your nearest hospital.

Heavy Vaginal Bleeding

If you are experiencing blood clots, heavy bleeding that is soaking through a pad in an hour – you should go to the ER as soon as you can.

Abdominal Pain

Lower abdominal pain can be a cause for concern during your first trimester as well. You’ll want to go to the ER or see your doctor right away.

Lower Back Pain

If accompanied with the above two symptoms – you should have this also checked out. Having lower back pain alone can be an indicator of other things like – your stretching body, UTI, or a sign of miscarriage and should all be reasons to go to your OB or nearest hospital.

The Changes Your Body Will Go Through In The First Trimester Of Pregnancy

During this time, you may not notice a lot of outward changes but inside your body is working overtime to make your baby, to expand your uterus, and to help you birth your baby.

Let’s dive right into the week to week on what to expect in the first trimester.

First Trimester Pregnancy Symptoms Week By Week

Now that you know which symptoms are fairly common during the first trimester – you may be wondering what you can expect each week of your pregnancy during the early months. Let’s break it down week by week.

Week 4

During this time frame you may experience: missed period, slight bloating and light vaginal bleeding.

Week 5

Now it is when most women find out they are expecting you may start to notice: nausea, morning sickness and sore and tender breasts.

Week 6

During the sixth week of pregnancy moms-to-be may experience things like: Bloating, weight gain, firmer uterus, firmer lower pubic region.

Week 7

Now you may have food aversions and smell aversion which warrant for morning sickness. You may also feel overly tired and drained each afternoon.

Week 8

This eighth week can be a little odd for your partner. You are going to go through mood swings and your body is now pumping 50% more blood than before.

Week 9

This is going to be a fun week, you may be experiencing things like heart burn, nausea, slight weight gain, and wider hips. You can still have morning sickness (or it might be getting less severe now).

Week 10

Your uterus is about the size of a grapefruit now and will only continue getting larger. You still may not be showing and you’ll still have some of the same symptoms from weeks 7- now. But don’t worry they will be going soon

Week 11

Hormones are your new frienemy. They will cause your hair and nails to grow faster (and stronger) #yes. But they can also cause things like oily skin, and pregnancy acne. And yes it is normal to get pregnancy acne – try to cut down on the sugar and caffeine and try using pregnancy safe face / body wash.

Week 12

Almost like a sign from above – you may start to experience less pregnancy symptoms now that the second trimester is approaching. You can also start to get creative and find ways to announce your pregnancy.

The symptoms you can expect this week are: bloating, acne, pregnancy glow which is really extra oil in the face and sweating.

Changes In Your Emotions

As you guessed – this time of your life is going to be filled with a lot of new emotions. Some of which you may not expect.

For example a lot of first time expecting moms feel scared, anxious, and nervous when they find out they are pregnant. It is normal to have these wide range of emotions. You can be happy you’re pregnant and still feel like ‘what is going on, what will I do’

Your mental health is just as important as your physical health. If you start to feel changes in your mood like depression, thoughts of suicide, anger towards yourself and your unborn child – you should mention this to your doctor.

Antepartum depression is a thing that not many moms know about. It is when you feel depression during pregnancy (and you did not have depression before). It is serious and it is not your fault that you feel this way.

Here is the number for the suicide prevention hotline:  1-800-273-8255

Your First Prenatal Visit: What To Expect / What Tests Will Be Done

As you approach weeks 8-10 you may have your first prenatal visit with your midwife or OBGYN. During each of your prenatal visits some things will remain the same.

Here is what you can expect from each and every visit:

  • Urine test
  • Weight tracking
  • Blood pressure check

These 3 things will be done at each visit no matter which week of pregnancy you are in.

Now for the first visit however you are going to have a little more work done.

  • Papsmear
  • Blood work
  • History Of Illness
  • History of Pregnancy
  • General check up
  • STD tests
  • Blood sugar tests
  • Ultrasound

If they don’t perform an ultrasound but use a Doppler to hear baby’s heart beat than that is normal as well.

Why Is The First Trimester The Most Critical?

The first few months of your pregnancy are considered the most critical because most of baby’s major body parts are formed during this time. Meaning that the chance for defects and miscarriage is high.

It is important that you stop doing certain activities and start forming healthy relationships with your body to make sure you and baby are healthy.

What Should I Avoid Doing During The First Trimester Of Pregnancy

  • Drugs & Alcohol
  • Lifting Heavy Objects
  • High Mercury Fish
  • Caffeine
  • Unwashed Produce
  • Raw Eggs
  • Cold Deli Meats
  • Changing Kitty Litter
  • High Heels
  • Stomach / Back Massage
  • Certain Abdominal Exercises
  • Fake Tans
  • Bleaching Hair

You might be thinking this is a big list of things that you shouldn’t do. But what can YOU do during the first trimester?

First Trimester To-Do Checklist

  • Make appointment to see your doctor
  • Buy prenatal vitamins
  • Tell your partner the good news
  • Research your works maternity leave policy’s
  • Check your insurance
  • Take more naps
  • Eat frequent mini meals
  • Healthy snacks
  • Increase your water intake
  • Pee constantly

You can still have fun and do a lot of the things you normally do – just take it easy and rest as much as you can these first three months. During the second trimester you’ll start to feel better and have more energy.

Get a full first trimester to-do list for free when you get access to my Pregnancy Resource Library! Which you can do by clicking here.

What Is A High Risk Pregnancy?

Normally, you will be seen by your doctor after a few weeks of being pregnant. However if you have a high risk pregnancy you may be seen earlier.

A high risk pregnancy is when you have factors in your history that can complicate your pregnancy. Things like:

  • Being younger Than 17
  • Older Than 35
  • History of Miscarriage
  • Diabetes
  • High Blood Pressure
  • Kidney Disease
  • STD’s
  • Autoimmune Disease’s

When you make your first appointment and you have any of the ‘risk’ factors make sure to mention it to your doctor in order to get the proper care you need when you go in.

When To Announce Your Pregnancy

Normally, you’ll want to wait till the end of your first trimester (3 months) to announce your pregnancy to family, friends, social media and work.

You’ll want to do this in order to bypass the miscarriage rate. Once you hit the 13th week of pregnancy the chance of miscarriage goes down to less than 1%.

You can also go ahead and tell everyone the moment you find out. This is completely up to you and your partner.

How To Afford Baby / Insurance FAQ

It can feel a little scary when you are living pay check to pay check and expecting a baby for the first time. (I’ve been in that very situation)

Here are a few things that can help you start a budget and save lots of money during your whole pregnancy.

Now once you confirm your pregnancy – you’ll want to go ahead and call your insurance and verify what they cover and which doctor you can go to for prenatal care.

Here are a few questions you may want to ask your insurance carrier:

  • How many ultrasounds am I covered for?
  • Is my current doctor covered for me to get prenatal care?
  • How much is my deductible?
  • When do I have to meet my deductible by?
  • Does my insurance cover maternity leave?
  • Does my insurance cover prenatal vitamins?
  • How can I get a free breast pump?

Wow, I know we went through a lot of information. And it might feel a little overwhelming right now because of information overload. That is okay and normal.

Make sure you save this post – so you can come back and go through it slowly as you progress through the first trimester.

Want To Remember This Post? Pin The Image Below To Your Favorite Pinterest Board.

what to expect the first trimester of pregnancy
first trimester of pregnancy

First Trimester OF Pregnancy – The Ultimate Guide

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Antepartum Depression: What To Know About Depression During Pregnancy

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Rosaura is the mom blogger who helps first time pregnant and postpartum moms find the solutions to their everyday problems. From first finding out you're pregnant to giving birth and baby care, she has you covered.