A New Mom’s Guide to the Three Stages of Pregnancy

Congratulations, you’re pregnant! This will be one of the most exciting times of your life. Right now, you are probably nervous and curious about what to expect.

Nearly 123 million women get pregnant each year, so you are certainly not alone even if it may feel like it right now.

Let’s help ease some of your anxiety by going over what to expect during the three stages of pregnancy. Keep reading to learn about the different trimester stages, symptoms, baby development, and procedures during your 9-month journey to motherhood.

The Different Trimesters

You may wonder how long does each trimester lasts? The typical full-term pregnancy is about 40 weeks and is group into three stages known as trimesters. You, along with your baby, will go through major changes during each of these 12- to 13- week phases:

  • 1st Trimester: Conception to 12 weeks
  • 2nd Trimester: Week 13 to week 27
  • 3rd Trimester: Week 28 to birth

All pregnancies are different, so you may have symptoms that others do not. You may experience some symptoms when your hormones change and the baby grows.

First Trimester

The egg is fertilized and then implants to the uterus. The baby is just an embryo with just two layers of cells. From these two layers, the baby develops all body parts and organs.

Your Changes

The first change you may notice during this trimester is missing your period, which is usually one of the first indicators you are pregnant. Your hormones are surging and changes affect just about every part of your body. It is important to make sure you consult a doctor at this stage, in order to establish whether or not you are pregnant, and whether or not the baby and you are going to be healthy. If at this stage you are told by a doctor having a baby could impact on your health, or that they are noticing complications, Your Choices and other providers offer free ultrasounds that are specifically used to confirm the presence of a viable, uterine pregnancy, and you will be able to establish if the pregnancy is viable and is likely to continue normally, keeping you and baby healthy.

Symptoms you may experience include:

  • Tender breasts
  • Nausea or vomiting (known as morning sickness)
  • Extreme fatigue
  • Food aversions and cravings
  • Mood swings

At the end of this trimester, your uterus will start growing outside of your pelvic cavity. This is what causes your body to look pregnant. You may also notice less pressure on the bladder until the baby gets even larger.

You should take good care of yourself. This means you may need to go to bed earlier to get more rest. You may also need to eat smaller meals throughout the day to help combat nausea.

Baby’s Development

The brain and spinal cord start developing at about 4 weeks. Around week 8, your baby’s heart forms and beats with a regular rhythm.

Around week 6, your baby will sprout arms, legs, hands, and feet. Wondering when you will know the sex of the baby? The external sex organs form and reveal at around week 12.

The baby grows rather quickly during this trimester and averages about 3 inches long at the end of week 12 (or about the size of a plum).


Your doctor will probably confirm your pregnancy with another urine test. You will also get your initial blood workup to check for any abnormalities. You may even get your first ultrasound.

There are other tests that can be done during pregnancy. For those who may have curiosity regarding the gender of the baby, you might find it useful to complete a prenatal gender test in new zealand, or wherever you live, to answer that burning question.

Second Trimester

If you experience morning sickness during the first trimester, you may be relieved to know it will most likely get better in the second trimester. This is because your body has adjusted to all those hormone changes. You may also sleep better and have more energy.

Another exciting time in the second trimester is feeling your baby’s first moves.

Your Changes

You may feel some swelling in your feet and ankles along with leg cramps. As your belly grows, you may feel some pressure and achiness in your abdomen.  Unfortunately, you may also get some congestion like a cold.

Some women get hemorrhoids during this trimester. If you do, talk to your doctor about relief. Try to drink plenty of water and eat lots of fruits and vegetables.

Varicose veins are also another symptom that may appear at this stage.

Try to stay active during this stage to reduce swelling. You can walk or even swim for exercise. Try to eat healthy foods and elevate your feet when resting.

Baby’s Development

Your baby will have major growth spurts. Around week 16, your baby will double his or her weight and add inches. The baby will also start to move her arms and legs, so you’ll feel some jabs and kicks.

Other major developments in this trimester include:

  • Nails grow on fingers and toes
  • The baby begins to suck and swallow (may even taste some of the food you eat)
  • The brain has the biggest and most important growth
  • Eyelids can open
  • Eyelashes and eyebrows are visible

At the end of this trimester, the baby weighs about 2-3 pounds. He is also about 13-16 inches long (or the size of rutabaga).


During the second trimester, you will get the full anatomy ultrasound screening to check your baby’s development. They will also do a quad screen to check risk factors and do the glucose test to look for gestational diabetes, which is rather common.

Third Trimester

You are now in the final countdown. Your abdomen will also stretch as you finish this stage, so it may feel tight. Your uterus grows to accommodate that baby and can put pressure on your bladder once again.

You may also notice that your fatigue has returned. You may find it harder to get comfortable at night.

Your Changes

You may experience some of these symptoms in the final trimester:

  • Stretch marks
  • Indigestion and heartburn
  • Constipation
  • Leaky breasts
  • Vivid dreams
  • Practice contractions or Braxton Hicks

It’s important to start practicing Kegel exercises to strengthen your pelvic floor. You may also want to sleep on your left side for the best circulation. Also, try adding pillows between your legs to get more comfortable.

Baby’s Development

Your baby is on the fast track in the last weeks of pregnancy. The brain continues developing along with the lungs and kidneys.

The baby can now see and hear. In the last part of the trimester, babies can also cry and suck their thumbs.

Your baby will prepare for delivery by turning head-down and begin dropping. The average birth weight is 6-9 pounds and about 9-21 inches long (the size of a watermelon or jackfruit).


Your doctor will do any stress tests and monitor the baby’s heartbeat. At each appointment, your doctor will screen your blood pressure to watch for any spikes. They will also do a Strep B test to see if any antibiotics are needed after birth.

Enjoy Your Three Stages of Pregnancy

Being pregnant is a journey you probably won’t forget. Through each of these three stages of pregnancy, keep a journal of your thoughts that you can share with your child later in life.

Want to learn more about parenting? Keep checking out our site for advice and get ideas on what to do when the baby is here.