Uterus During Pregnancy - Its Size, Changes and Role

Uterus Size During Pregnancy

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Debolina Raja Gupta

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During pregnancy, your body changes both from the inside, and the outside. While some of these changes are obvious, others are subtle. As your pregnancy progresses, you will start to feel the subtle changes as well. One part of your body that will change the most is your uterus.

Uterus is a vital organ for a woman to get pregnant, and even after she gets pregnant. It is a sack that holds your baby carefully inside your body, until it is time for your child to come out. So, if you would like to know more about uterus, and the changes it undergoes during pregnancy, take some time to read the information here.

The Role Of Your Uterus:

It is true that your uterus plays an important part in your pregnancy, but its role is not just limited to that. Here are a few other things that your uterus does, which are equally important:

1. Supports The Flow Of Blood:

Your uterus helps the blood to flow to your ovaries.

2. Supports Your Other Internal Organs:

Also, your uterus also provides support to your other organs, such as your vagina, your rectum, and even your bladder.

3. Important For Sexual Functions:

Your uterus also plays a very important role in sexual functions. It is that part of your body responsible for triggering those orgasms that you experience after a session of sex.

[ Read: Precautions During First Trimester Of Pregnancy ]

The Role Of Your Uterus During Pregnancy:

One part of your body which plays a very important part while you are pregnant is your uterus. It is one of the most important organs of your reproductive system. Here are a few things that your uterus helps your body with while you are pregnant:

1. Holds The Fertilized Egg:

Your uterus is the place where the fertilized egg gets implanted.

2. Nestles Your Unborn Baby Through The Months Of Pregnancy:

Your uterus is also the place where your unborn baby will stay during your pregnancy and develop through the various stages.

3. Grows Along With Your Unborn Baby’s Development:

As your uterus will hold your unborn baby through the pregnancy, it will also grow as your pregnancy progresses, to make more space for your growing baby. From the time that you get pregnant until the time that you deliver your baby, your uterus will go through a massive change in size.

[ Read: When Do You Start Showing Pregnancy ]

What Your Uterus Is Made Up Of:

Your uterus is made up of very smooth muscles lined with various glands. The muscles of your uterus can contract while you have an orgasm, during your monthly menstrual periods, and also while you get into labor. Each month, the glands in the walls of your uterine muscles start to become thicker. It will happen as a result of the various hormones that your body will produce and release through the month. If you do not become pregnant, the glands will shed off when you have your menstrual cycle in the month. The part of your uterus that extends all the way into your vagina is known as the cervix. It is made up of various fibromuscular tissues. The cervix grows towards the end of your pregnancy term and helps your baby to move out of your uterus and come outside at the time of the birth.

The Regular Size Of Your Uterus:

There is no same size fits all when it comes to a uterus, and the size of the uterus varies from female to female. However, it is true that there is some size range in which any female’s uterus will fit in, no matter what the individual size. At the time of birth, the size of the uterus is very small, barely the size of the thumb of an adult. A woman who has never been through pregnancy will also have a smaller uterus size as compared to a woman who has been pregnant at some time. In most cases, the uterus will weigh anything between something as less as 30 gm. (which is approximately 0.6 pounds) and something as high as 100 gm. (which is approximately .22 pounds).

Uterus Size During Pregnancy – Trimester Wise Changes :

Before you become pregnant, your uterus will be no bigger than a pear. It will be about three cm. in thickness and will measure about 4.5 cm. in width. At this point, your uterus will be about 7.6 cm long. However, as you pass through the months of your pregnancy, your uterus will go through a marked change in size. Here is a look at how your uterus will grow through each trimester:

1. Your Uterus In The First Trimester:

  • Until you are in the 12th week of your pregnancy, your uterus will be approximately the size of a grapefruit.
  • As you move on through the weeks of your pregnancy, your unborn baby will start developing outside your pelvic area. However, your baby’s size will still be small enough so that your unborn baby will be able to fit in comfortably in your pelvic area.
  • If you are carrying more than one baby, such as in the case of twins, triplets or multiples, your uterus will grow faster than women who are carrying only one baby.
  • During this time, your doctor will be able to feel your uterus in a checkup by touching your belly.

[ Read: Pregnancy Week By Week ]

2. Your Uterus In The Second Trimester:

  • By the time you are in your second trimester and growing, your uterus will considerably grow in size. From being just the size of a grapefruit, it will now grow big enough to become the size of a papaya.
  • At this stage, your uterus will no longer be small enough to fit inside your pelvis. And, it will move to an area which will be between your breasts and your navel.
  • Your growing uterus will now also start to create pressure and push other organs, making them move away from the locations where they normally are placed.
  • As a result of all the pushing that your uterus does to the other organs and the resultant movement that the organs go through, you will feel tension in the ligaments and muscles around the area. At this time, you will feel the discomfort and will also start to feel pain throughout your body.
  • Do not worry as all this is a normal part of the pregnancy and will not cause any health issues or concerns.
  • In some cases, as your uterus will exert pressure on the various organs, including your navel, you may see that your navel will pop outwards instead of being inward.
  • Around the time you are between the 18th and the 20th week of your pregnancy, your doctor will measure the distance between the top part of your uterus (which is known as the fundus) and your pubic bone. The measurement that your doctor will take is known as the fundal height. It will help your doctor to assess exactly how many weeks you are in your pregnancy. For instance, if the doctor measures the fundal height and the result is 30 cm, it will mean that you are 30 weeks pregnant.
  • In case you are pregnant for the first time, the results may vary, as your measurements may be a bit larger than otherwise.
  • The measurement of the fundal height and the size of your uterus will also help your doctor to determine if your pregnancy is progressing properly. In case the size of the uterus is too small or too big, it could result in certain pregnancy related complications. In case that happens, your doctor will refer some additional tests to find out the exact cause and the way to treat the same.

[ Read: Breast Changes During Pregnancy ]

3. Your Uterus In The Third Trimester:

By the time you are in your third trimester, your uterus will go through a huge overhaul in terms of its original size. From the size of a grapefruit when you were in your first trimester, your uterus will now be the size of a watermelon while you are in the third trimester.
By the time you reach towards your full term, your uterus will move on from your pubic area and almost till the bottom part of your rib cage.
Once you near your labor, your baby will drop in your pelvic area.

[ Read: Baby Fruit Size Comparision ]

4. Your Uterus After Birth:

Once you give birth, your uterus will gradually shrink back to its normal size, what it was before you became pregnant.
The process through which your uterus will return to its pre-pregnancy position as well as size is referred to as involution.
It will take about six to eight weeks for your uterus to return to its original size after you have given birth.

Measuring Your Uterus While You Are Pregnant:

While your doctor is the person who will measure your uterus while you are pregnant, you too can use a few simple ways to try out the same. Here are a few ways in which you can find out just how big your uterus is growing while you are pregnant:

1. Step 1:

  • Before you begin to take the measurement and see how much your uterus has grown, you will first have to get down in a comfortable position.
  • Lie down slowly on the floor or on the bed in a flat position, and on your back.
  • Make sure that you are comfortable and that you are not feeling any pain or dizziness.

2. Step 2:

  • The first step now will be to locate your uterus and your fundus.
  • Touch your stomach in such a way that you can feel your uterus.
  • If you are about 20 weeks pregnant, you will be able to feel your uterus just below your navel area.
  • If you are more than 20 weeks pregnant, you will be able to feel your uterus just above your navel area.
  • You will be able to feel your uterus as a hard part on the inside of your tummy area, and it will also feel round and smooth at the same time.
  • Move your hand a little to feel the top of your uterus, which is also known as the fundus.
  • In most cases, it will be easier for you to feel your uterus after you are 20 weeks in your pregnancy.

[ Read: Facts About Baby Kicks During Pregnancy ]

3. Step 3:

  • For your next step, you will have to locate your pubic bone.
  • You will be able to locate your pubic bone in the area which is positioned just above your pubic hair line.
  • You will be able to feel a kind of bony tip on the top part. It is your pubic bone.

4.Step 4:

  • Once you have located your uterus or fundus, as well as your pubic bone, you can proceed to take the measurements.
  • Now carefully measure the distance between your fundus and your pubic bone.
  • The number that will get after taking the measurement is the same number as the number of weeks that you are pregnant for.
    In case you feel that there is a big discrepancy between the number that you get after taking the measurement and the approximate number of weeks that you think you are pregnant, do speak to your doctor to clear your doubts.

Make Sure Your Uterus Stays Healthy:

Your uterus plays a very important role in your pregnancy and in nurturing your unborn baby safely. It is very important that you ensure that your uterus is healthy and in good shape. Here are a few steps that you should take to keep your uterus in good health:

  • Make regular appointments with your doctor to check the health of your uterus.
  • Your doctor will refer you for a pap smear test to check for the presence of any abnormal cells on your cervix.
  • In some cases, your doctor will go ahead with an internal examination to check for the presence of any abnormalities in the uterus. Some such concerns that your doctor will be able to identify through an internal examination of your uterus are issues such as tumors in the fibroid or even cancer in the uterus.
  • In case you notice any bleeding, which is not part of your monthly menstrual periods, make sure that you talk about it with your doctor.
  • If you do experience very heavy bleeding while you are going through your monthly menstrual periods, or if you feel that the bleeding is very irregular, make sure you report the same to your doctor. Very heavy bleeding, irregular bleeding and abnormalities in bleeding are some of the first signs that you may be developing tumors in the fibroid, adenomyosis (it is a condition in which the inner lining of your uterus will break through the muscular wall of your uterus), or hyperplasia (it is a condition in which an organ or tissue grows exceptionally large and is the first stage of cancer).
  • If you feel any pain or discomfort in your uterine area, make sure you speak to your doctor about it. Almost as many as 50 percent women are affected with tumors in the fibroid. Even though they are mostly not cancerous, it can result in a lot of bleeding as well as a lot of pain. While women of any age can develop fibroids in the uterus, it is usually most common in women who are in their 30s and their 40s. While doctors are not really sure of what exactly causes fibroids in women, you will have a higher chance of getting affected if you have a family history of the same.
  • Most women who suffer from cancer of the uterus also face overweight issues. Make sure you eat right and include some form of exercise in your daily routine to take care of your weight and keep it healthy.

[ Read: Uterine Fibroids During Pregnancy ]

Other Changes In Your Uterus While You Are Pregnant:

When you become pregnant, your uterus will go through a massive change in its size. In addition to that, there also some other changes that will take place in your uterus through the months that you are pregnant. Here is a look at what other changes your uterus will be going through at this time:

1. Development Of The Corpus Luteum:

  • The corpus luteum is a small structure that will form as soon as the egg gets fertilized.
  • It will form a protective surrounding around your embryo and will release progesterone, which is one of the most important hormones of your pregnancy.
  • The corpus luteum will also aid in the growth of the lining around your uterine walls.

2. Formation Of The Placenta:

  • Your uterus will also help to develop the placenta, which will help to support and nurture your unborn baby.
  • The placenta will produce both the estrogen and the progesterone hormones, which will help in the change of size and positioning of the uterus.

[ Read: Cervical Length During Pregnancy ]

3. Blood Vessels Grow Bigger:

  • After about a month of your pregnancy, the blood vessels present in the lining of your uterus will grow bigger. As a result, it will make your uterine lining thicker.
  • It will aid in providing nourishment as well as support for your growing baby.

4. Cervix Becomes Softer:

  • Around the time you are four weeks pregnant, your cervix will begin to change in color and texture.
  • It will also develop a mucous plug about five weeks after your egg has fertilized.
  • The mucous plug will help to hold your uterus in place and keep it safe from any contamination from the outside.

5. A Change In The Lower Segment:

  • While you are pregnant, as your unborn baby grows with each passing month, your uterus will start to develop outside your pelvic area.
  • By the time you are about 12 weeks in your pregnancy, you will be able to feel the top of your uterus, which is known as the fundus.
  • By the time you are about 24 weeks in your pregnancy, your myometrium muscles will start to stretch towards the upper part. It will turn the upper part of your uterus thicker. The thinner layers of muscle that will be left behind are referred to as the lower segment.
  • The lower segment is the part that will help to keep your cervix and your upper segment separated.
  • The lower segment will help to absorb your dilated cervix when you enter your labor at the end of your pregnancy.
  • The muscles of your lower segment will form about a third of the lower part of your uterus. It is a weak layer of muscle and will often get a lower amount of blood supply as compared to the upper part of the uterus. As a result, if you have to go in for a cesarean delivery, the operation will not be performed on your upper segment.
  • The cut which will be made to bring your baby out during a cesarean operation will be made on the lower segment. Your doctor will make the cut right above your pubic hairline, where the blood flow is lesser as compared to the upper segment. As a result, it will help to prevent any instance of excessive bleeding.

[ Read: Tips To Maintain Healthy Weight During Pregnancy ]

6. A Change In Your Ligaments:

  • As you move from the start of your pregnancy towards the end stages of your pregnancy term, your uterus will lean towards your right side.
  • During this time, the various ligaments help to hold your uterus in place even as your uterus is stretching to accommodate your growing baby.
  • The ligaments will help to support your uterus and stabilize it and also help your unborn baby to move around inside.
  • At this stage, your ligaments will also experience a lot of strain, which will make you feel uncomfortable and will lead to pain in your stomach as well as some temporary pain in your groin area.
  • The type of pain that you will feel as a result is known as ligament pain. Do not worry as it is an absolutely normal part of your pregnancy and will ease once you have given birth.
  • You will also feel the pain very sharply if you do any sudden movements, such as coughing or sneezing.

There are a lot of changes that will happen in your uterus, from size to many other factors. Do not worry, as most of these are normal parts of your pregnancy and the uterus will also go back to its normal shape and size few weeks after the delivery.

Moms, if you have any further concerns, please make sure that you speak to your doctor about it.

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