Stage Of Pregnancy Trimesters and Due Date - Actionable Guide

Most pregnancies last about 40 weeks and are divided into three trimesters.

Each stage of pregnancy trimester brings different challenges and changes for both the mother and healthy babies.

In this article, we will explore the stages of pregnancy in detail, including what to expect during each one.

How Soon Can You Tell If You Are Pregnant?

The first trimester is from week one through 12 and includes conception, which is when the sperm fertilizes the egg.

Most women don't know they are pregnant until they miss a menstrual period.

Some may experience a pregnancy symptom as early as two weeks after conception.

So, Let's have a look at the early symptoms of pregnancy

Early Pregnancy Weight Gain

Pregnancy is a beautiful and amazing time in a woman's life.

It can also be a time of many physical changes, including weight gain.

Some women worry about how much weight they should gain during pregnancy, but there is no need to be concerned as long as you are eating healthy foods and getting enough exercise.

Pregnancy Weight Gain Distribution

When you are pregnant, you will gain weight. Most people will gain weight evenly throughout their pregnancy.

But some people will gain more weight at the beginning or end of their pregnancy.

This is called pregnancy weight gain distribution.

If you are pregnant, you should talk to your doctor about how much weight you should gain.

They will help you figure out a healthy pregnancy weight gain range for you.

The amount of weight you gain during pregnancy can affect your health and the health of your baby.

So it is important to stay within your recommended weight gain range.

Pregnancy Complications

Pregnancy can sometimes have problems. Some problems can cause symptoms.

These are some of the most common symptoms:

  • feeling sick or being sick

  • swollen breasts

  • having a headache

  • feeling tired all the time

  • having pain in your tummy, back or pelvis

  • passing water more often than usual

  • having a change in your bowel habits

  • feeling dizzy or faint.

If you have any of these symptoms, speak to your midwife or doctor as soon as possible.

They can help to find out what is causing the problem and give you treatment.

First Pregnancy Trimesters (0 to 13 Weeks)

The first trimester of pregnancy is a crucial time for the development of the fetus.

During this time, all of the major organs and systems are formed.

The heart begins to beat at around week five, and brain activity can be detected at week six.

By the end of the first trimester, the fetus is about three inches long and weighs about one ounce.

The first trimester is also a time of rapid change for the mother's body.

The levels of the hormone progesterone increase, which can cause fatigue and nausea also known as morning sickness.

The breasts may also become larger and more sensitive.

Some women may also experience mood swings and cravings during this time.

Although the first trimester can be challenging, it is an important time for both the mother and the baby's development.

With proper care, both will be healthy and ready for the next stage of pregnancy.

The fetus

During the first trimester of pregnancy, the fetus starts to grow.

It starts as a small seed and developing baby.

The baby's organs start developing and it begins to grow arms and legs.

This is the most critical time in the development of the baby.

The pregnant person

The pregnant person might feel sick in the morning. They might have to go to the bathroom a lot.

And they might feel tired all the time.

Changes in a Woman's Daily Routine

A woman's daily routine changes a lot during pregnancy:

Eating Better

You will need to eat more healthy foods to make sure the baby gets all the nutrients it needs.

You should eat a variety of fruits, vegetables, whole grains, and proteins.

You will also need to take a prenatal vitamin every day.

Getting More Rest

Pregnancy can be exhausting. You will need to get more rest to help your body recover from all the changes it is going through.

You may need to take a nap during the day or go to bed earlier at night.

Avoiding Harmful Activities

Some activities can be harmful to the baby, such as smoking, drinking alcohol, and using drugs.

You should avoid these activities during pregnancy.

You should also avoid activities that could cause you to fall, such as skiing or rock climbing.

If you have any questions about whether an activity is safe, you should seek medical advice.

The Baby at 4 Weeks

At 4 weeks, your baby is growing:

  • The nervous system (brain and spinal cord) has begun to take shape.

  • The heart begins to form.

  • Arm and leg buds begin to develop.

  • Your child is now a week old, 250 of an inch long, and an embryo.

The Baby at 8 Weeks

At 8 weeks, your baby is growing:

  • The embryo has formed all of the major organs.

  • The heart begins to beat. The limbs and upper body grow in length.

  • Fingers and toes are beginning to form. Sex organs are beginning to develop.

  • Features on the face begin to emerge.

  • The umbilical cord can be seen clearly.

  • Your kid is a fetus at the end of eight weeks, measuring approximately 1 inch long, weighing less than â…› ounce

The Baby at 12 Weeks

At 12 weeks, your baby is growing:

  • The nerves and muscles begin to collaborate. Your baby can now make a fist.

  • The external sex organs reveal whether your baby is a boy or a girl.

  • The eyelids are closed in order the eyes from injury. They will not reopen until week 28.

  • Your baby's head is still developing, and he or she has now grown to be about three inches long and weighs a little more than an ounce.

Second Trimester (14 to 26 Weeks)

The second trimester of pregnancy is often considered the “golden period” because pregnant women often feel their best during this time.

They have more energy and their skin begins to glow.

However, the second trimester is also when many pregnant women begin to feel overwhelmed.

The constant change in their bodies can be exhausting, and they may worry about how they will cope with the demands of motherhood.

Despite the challenges, the second trimester is a special time for expectant mothers and their families.

This is when they can start to enjoy the pregnancy and bond with their baby.

The fetus

The second trimester of pregnancy is when the fetus grows more.

The baby's heart continues to beat and the lungs begin to develop.

The baby starts to move and can kick its legs.

The pregnant person

During the second trimester, the pregnant person might feel more tired than before.

They may also have to go to the bathroom more often.

There is also a higher chance of having a miscarriage during this time.

The Baby at 16 Weeks

At 16 weeks, your baby is growing:

  • The muscular system develops.

  • The skin begins to form and is translucent.

  • Meconium forms in your baby's intestinal tract.

  • This will be your baby's first bowel movement.

  • Your baby makes sucking motions with his mouth (sucking reflex).

  • Your child is about 4 to 5 inches long and weighs around 3 ounces when he or she is born prematurely.

The Baby at 20 Weeks

At 20 weeks, your baby is growing:

  • Your baby is more active.

  • You could feel a movement or a kick. Your baby is covered in lanugo hair and a waxy protecting layer called vernix.

  • Eyebrows, eyelashes, fingernails, and toenails have all appeared.

  • Your baby can even scratch itself as well.

  • Your infant can hear and chew as well as swallow.

The Baby at 24 Weeks

At 24 weeks, your baby is growing:

  • The baby's bone marrow starts to make blood cells.

  • Your baby's tongue develops taste buds.

  • Footprints and fingerprints have developed.

  • Your baby's hair grows on his or her head.

  • The lungs have yet to be developed.

  • Your baby's sleep cycle is consistent.

  • His testicles begin to fall into the scrotum if your baby is a boy.

  • If your baby is a girl, her uterus and ovaries are intact, and a lifetime supply of eggs has been created in her ovaries.

  • A newborn baby is born with a lot of fat, but it amounts to only around 1.5 pounds after one week and is 12 inches long.

Third Trimester (27 to 40 Weeks)

The third trimester of pregnancy (27 to 40 weeks) is a time of rapid development for the baby.

During this trimester, the baby's brain and nervous system continue to develop, and the organs mature and begin to function.

The lungs are one of the last organs to mature, and they may not be fully developed until after birth.

For this reason, some babies born before 40 weeks may need help breathing.

As the date approaches, the baby begins to move into the head-down position in preparation for labor and the expected delivery date.

The mother may also experience some changes during this trimester, including an increase in vaginal discharge, Braxton hicks contractions, and fatigue.

This is a normal part of third-trimester pregnancy and is nothing to be concerned about.

However, if you experience any bleeding or abdominal pain, please contact your healthcare provider immediately.

The fetus

The third trimester of pregnancy is when the baby grows even more. The baby's heart continues to beat and the lungs continue to develop.

The baby starts to move more and can now suck its thumb.

The pregnant person

The pregnant person is almost done with the pregnancy.

The person's face might be a little bit swollen and they might have gained some weight a bit extra, especially in the third trimester of pregnancy.

The person's belly is big and round.

The person's breasts might be tender and they might have some nausea.

Changes as the Due Date Approaches

Here are a few of the more common reasons why your baby's arrival day may be postponed:

  • You have irregular periods: Do you find that your monthly get away from you every once in a while? It's difficult to determine a date using the date-of-last menstrual period approach for women with irregular cycles, which is why an ultrasound scan is frequently required to calculate gestational age.

  • Your first date relied on Doppler: Not an ultrasound, but a Doppler heartbeat monitor is used to confirm most pregnancies.

    If this was you, it's possible your doctor's initial timetable was incorrect because an early ultrasound (usually done at 6 to 9 weeks), which can determine the size of the embryo or fetus, might have been performed.

  • In the second trimester, your first ultrasound was performed: Did you get your first ultrasound in your second trimester?

    If this is the case, it's another cause to why your date has changed. According to the American College of Obstetrics and Gynecology (ACOG), ultrasonic exams performed during the first trimester (but not the second) provide the most precise predictions.

  • Your fundal height is above average: At each appointment, you'll get a fundal measurement, which is the distance from the top of your pubic bone to the top of your uterus.

    This number is highly linked to how far along you are because it indicates how far along your uterus has grown.

    It's possible that your uterine size doesn't match up with normal growth charts.

  • You have abnormal AFP levels: A blood test for AFP will be ordered during weeks 14-22, most likely to screen for AFP - known as Alpha-fetoprotein, a liver and yolk sac protein that is usually produced during pregnancy.

    (This is sometimes included in the quad screening.) While elevated levels of AFP indicate a possible genetic abnormality, the number one reason is due

  • Fetal heart tones: When did a provider hear the baby's heartbeat, and what instrument did they use?

  • Fundal height: The fundus (the top of the uterus) might differ from what you expected based on your estimated birth date.

  • Quickening: When did you first detect movement from your baby?

Other factors, such as the discovery of a twin pregnancy, uterine anomaly, and your weight can also affect the calculation of your date

The Baby at 32 Weeks

At 32 weeks, your baby is growing:

  • Your baby's bones are still soft, though they are now completely formed.

  • Kicking and moving become more frequent.

  • Your baby's eyes can open and close but it's practicing now!

  • Your baby's body begins to accumulate vital minerals, including iron and calcium.

  • Lanugo (thin hair) begins to shed.

  • Your baby is accumulating around 1 pound a week, weighs between 4 and 4â…” pounds, and is approximately 15 to 17 inches long.

The Baby at 36 Weeks

At 36 weeks, your baby is growing:

  • The protective waxy covering (vernix) thickens.

  • Body fat levels rise.

  • Your kid is growing bigger and has less room to move about.

  • Your infant is between 16 and 19 inches long and weighs about 6 to 6½ pounds.

The Baby at 37 to 40 Weeks

At 37-40 weeks, your baby is growing:

  • Your baby is considered full term at the end of 37 weeks.

  • The organs in your infant can operate on their own.

  • Your baby may change positions for birth as you approach your delivery date.

  • The average birth weight is between 6 and 9 pounds, with a typical length of 19 to 21 inches. The majority of full-term babies fall within

The fourth trimester: Postpartum

The fourth trimester is the period immediately following childbirth when the mother and baby are adapting to life outside the womb.

During this time, the mother's body is going through several changes, both physical and hormonal.

The baby, too, is adjusting to life in the world and learning to feed, sleep, and cry.

It can be a challenging time for both mother and child, but it is also a time of great wonder and joy.

The fourth trimester is a special time that should be cherished and celebrated.

Suicide prevention

Suicide prevention is important during pregnancy because it can be a difficult time for some women.

There are ways to get help if you are feeling suicidal, so please don't hesitate to reach out for support.

If you are feeling suicidal, the first thing you should do is tell someone who can help. This could be your partner, a friend, a family member, or a health care provider.

If you don't feel comfortable talking to someone you know, there are also hotlines you can call, like the National Suicide Prevention Lifeline at 1-800-273-8255.

Once you have told someone about your suicidal thoughts, they can help you create a safety plan.

This is a plan to keep you safe from harming yourself.

It will include things like who to call if you are feeling suicidal, what to do to make yourself feel better, and how to avoid triggers that might make you want to harm yourself.

If you are pregnant and feeling suicidal, please know that you are not alone. Help is available, and you can get through this tough time.

Pregnancy Symptoms: 10 Early Signs That You May Be Pregnant

If you're wondering whether you might be pregnant, take a look at these 10 early signs and symptoms of pregnancy.

You may not experience all of them, but some are quite common.

1. Missed Period: A missed period is usually the first sign that you might be pregnant.

Most women have a 28 to the 32-day menstrual cycle, so a missed period can be an early sign of pregnancy.

2. Nausea and Vomiting: Nausea and vomiting, also known as "morning sickness," is another common early symptom of pregnancy.

It usually starts around the sixth week of pregnancy and goes away by the end of the first trimester.

3. Breast Tenderness: Breast tenderness is another common early symptom of pregnancy.

It is caused by the increased hormone levels in your body and usually goes away after the first trimester.

4. Fatigue: Fatigue is a common symptom during pregnancy, especially in the first trimester.

This is caused by the increased hormone levels in your body and the extra energy that your body is using to support the growing baby.

5. Frequent Urination: Frequent urination is another common early symptom of pregnancy.

It is caused by the increased hormone levels in your body and the pressure of the growing uterus on your bladder.

6. Foods Cravings and Aversions: Many women experience food cravings and aversions during pregnancy.

This is thought to be caused by the hormonal changes in your body.

7. Heartburn: Heartburn is a common symptom during pregnancy, especially in the third trimester.

It is caused by the pressure of the growing uterus on your stomach and the relaxation of the valve that separates your stomach from your esophagus.

8. Constipation: Constipation is a common symptom during pregnancy, especially in the third trimester.

It is caused by the pressure of the growing uterus on your rectum and the relaxation of your bowel muscles.

9. Dizziness and Fainting: Dizziness and fainting are common symptoms during pregnancy, especially in the first trimester.

They are caused by the low blood sugar levels in your body and increased hormone levels.

10. Headaches: Headaches are a common symptom during pregnancy, especially in the first trimester.

They are caused by the increased hormone levels in your body and the changes in your blood vessels.


Pregnancy is an amazing time in a woman's life. Every pregnancy is different, but each one brings its challenges and joys.

By understanding the four trimesters of pregnancy, you can be better prepared for what lies ahead. And, knowing your estimated due date will help you plan for the big day.

So, there you have it! Everything you need to know about the stages of pregnancy and due date calculation.

We hope this article has been helpful. If you have any questions or comments, please feel free to leave them below.

And, as always, please consult with your healthcare provider before making any decisions about your pregnancy.

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