Normal 40 weeks pregnancy and ultrasound, your complete guide

Normal 40 weeks pregnancy and ultrasound, your complete guide


Hello to all my precious mommies-to-be.  I am so excited for today’s post, you finally made it to the end of your pregnancy, and this will be the last post for the weekly pregnancy series here on my blog. Today I am going to give all the information you need to know about your pregnancy and ultrasound at 40 weeks. We will be talking about Baby growth, Normal pregnancy symptoms, Fetal development at 40 weeks, Doctor visits, Signs of labor, Labor and delivery (Vaginal and C-section), also some useful tips for you at 40 weeks, are you ready, let’s begin.

At 40 weeks pregnant, you are officially at full-term, you have been pregnant for 9 months already. At this point you are about to go into labor at any time, the most you have left is one week perhaps 2.

Did you know that statistically:

The average first-time mom has their babies at 40 to 41 weeks.
The average second-time mom has their babies at 39 weeks. About 57% of second-time moms delivered their babies on or before their due date.
For mothers with more than one previous birth, the delivery was at 38 weeks 5 days. 58% of these moms delivered their babies on or before their due date.

However, since about 30 percent of all pregnancies last longer than 40 weeks more testing such as Biophysical profile and Non-stress will still be required. These test will give your doctor information about to give you a few more days/weeks versus induce childbirth immediately. If you are expecting twins, you probably have your babies by now. Majority of twin pregnancy have induction or C-section somewhere between 36 to 38 weeks.

40 weeks pregnancy and ultrasound

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How Big Is Your Baby at 40 Weeks?

Your baby at 40 weeks will be as big as a Jackfruit. The average 40-week fetus weighs about 7.5 lbs.. or about 3400 grams, and measures about 36 centimeters long.

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Read related posts to read after.

Normal 39 weeks pregnancy and ultrasound, your complete guide.

Second trimester to do list, getting ready for the new baby.

Tips to practice mindfulness as a parent, the benefits of mindfulness.

Normal pregnancy symptoms at 40 weeks!

Contractions: Braxton Hicks contractions will eventually turn into the real contractions. So if it feeling a lot of them, start timing them to see how far apart they are. If they get closer together, you’re in an early stage of labor.

Insomnia or trouble sleeping: With all the hormonal changes, midnight bathroom trips, leg cramps, heartburn and your big belly, it’s no wonder sleep is a luxury at this time. Try to find a sleeping routine that works for you. Anything from soothing music, a warm bath, reading a book, or a good massage will do. Avoid near bedtime caffeine and exercises. Remember you and the baby need to rest.

Swollen feet and ankles: You’re 40 weeks pregnant, you have the perfect excuse to sit back and put up your feet as much as possible. Take regular walks though, to keep your blood flowing and reduce the swelling.

Urge to nest: Nesting is another symptom that will be with you for some time before the baby gets home. Remember don’t go too crazy. Save energy for the delivery day. Instead, try to start early to clean the house, wash baby clothes, organize, etc. and before delivery try to prepare for the postpartum stage. Pamper yourself too and have some REST.

Leaking colostrum from your breasts: Colostrum, the first milk your baby will get when born, it contains more protein but less fat and sugar than more mature breast milk, making it easier for baby to digest in the first few days after birth. It’s also full of antibodies (immunoglobin A, or IgA) your baby didn’t encounter in the womb which help protect her from germs that can infect the mucous membranes of her throat, lungs, and intestines.

As you can see the majority of these symptoms has everything to do with the size of your belly, I know this is the most uncomfortable part of the pregnancy, at least it was for me. Please be patient, this is a temporary stage, everything will be good after you have the baby.

My Amazon picks for this time of the pregnancy, the list of must-have or necessities for your newborn.


Carrying the baby.

Baby necessities.

Soothing and entertainment.

Fetal development at 40-weeks!!

Your baby is still gaining half an ounce of fat each day.

The lanugo and vernix are almost completely gone.

Your baby, if it’s not on Breech position( Sitting ) is probably on the right position for birth, which is head-down facing to your back.

You are still providing to your baby with antibodies through the placenta. And even after birth, you still will be doing that through the breast milk. This process will protect your baby from bacteria and germs for at least the first 6 months of life until his immune system is ready to work on its own.

The baby’s lungs have enough surfactant at this time. Surfactant is naturally made in the lungs between 24 and 35 weeks gestation. This is between the 6th and 8th months of pregnancy. By 35 weeks most babies have enough surfactant to breathe well outside the uterus.

What to know about doctor visits?

You are still seeing your doctor on a weekly basis, the Delivery day can probably happen any day now.

You will be having pelvic exams, to check your cervix for dilation (opening) and effacement (thinning) both signs your body is readying for labor.

At this time you need to be alert for signs of labor, and still keep track of baby movements.

Signs of labor might include.

Rupture of the membranes (water breaking).

Diarrhea or nausea (many women experience these types of digestive issues just before the onset of labor).

Nesting instinct.

The loss of the mucous plug (the mucus seals the opening of the uterus).

Bloody vaginal discharge (your capillaries rupture from the dilation and effacement of your cervix, causing any discharge to appear pink or red-tinged).

Regular contractions: If your belly’s tightening and has been repeatedly for some time, start timing the contractions. If they keep coming and the time between them keeps getting shorter, you’re in the beginning stage of labor. Just how long this stage lasts will vary from mom to mom, so keep your OB updated, and follow his directions for getting to the hospital by the time you progress into active labor.

For as long as you remain pregnant, a Biophysical profile and a Non-stress test will be  need it.

The Biophysical profile will check the baby‘s breathing, movement, muscle tone, heart rate, and amniotic fluid, and all of this information will be scored. In some cases, the result of the biophysical profile could make your doctor decide to deliver baby earlier or wait more time.

The Non-stress test will check your baby’s movement, heartbeat, and contractions. It notes changes in heart rhythm when your baby goes from resting to moving, or during contractions if you’re in labor. Your baby’s heart should beat faster when active just like yours. The NST can reassure you that your baby is healthy and getting enough oxygen.

For reading more about Non-stress test check this link.

Important information about Labor.

Like every mom and baby, every labor experience is unique.

Listening to your body’s signal, intuition and trusting your ability to give birth can help your labor progress.

In the beginning of labor, the contractions tend to be mild and irregularly spaced, and thus labor progresses slowly, especially for first-time moms.

It can take 6 to 8 hours (sometimes even more) for your cervix to dilate up to a diameter of 4 centimeters, therefore that’s a good time to stay at home. No need to rush to the hospital yet, try to eat an easy-to-digest meal, take a shower, rest if you can, get ready to go to the hospital in a few hours, and don’t forget to drink a lot of water, try to avoid caffeinated and sugary drinks.

The next phase of labor usually progresses more quickly, it only takes 20 to 90 minutes to your cervix to go from 4 centimeters to 10 centimeters, usually this phase is called Transitioning phase and usually, you’ll feel very warm.

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40 weeks pregnancy information and ultrasound

Finally delivery.

The second stage of labor is Delivering your baby.

You may have felt an overwhelming urge to push, and now its the time push.

Trying different positions, if your doctor or midwife allows you, this can ease your pain and give you more control over the pushing part. Including your partner in this part is very important as you both are experiencing the most surreal and mesmerizing experience in the life of a human being, having a baby.

Always the birth of your baby’s head is the most difficult part, followed quickly by the rest of the body, and finally the placenta.

Now the baby that you have been nurturing inside your belly all these months is finally in your arms, WELCOME TO MOTHERHOOD.

Birth by C-section.

Now for all my C-section mamas, don’t feel overwhelmed or sad if you need to have a C-section. I have 2 C-sections myself and I can tell you that, your experience will be as magical and unique as a Vaginal birth.

Here is some more information for you about C-section.

How is a C-section done?

Once the Epidural anesthesia has taken effect, your belly will be swabbed with an antiseptic, and the doctor will most likely make a small, horizontal incision in the skin above your pubic bone (usually known as the “bikini cut”).

The doctor will cut through the underlying tissue, slowly working his way down to the uterus. When he finally reaches your abdominal muscles, he’ll separate them, usually manually rather than cutting through them and spread them apart to expose the uterus that lies underneath.

When the doctor reaches your uterus, he’ll probably make a horizontal cut in the lower section of it. This is called a low-transverse uterine incision.

Then the doctor will get and pull out your baby. Once the cord is cut, you’ll have a chance to see the baby briefly before he’s handed off to a pediatrician or nurse. While the staff is examining your newborn, the doctor will deliver your placenta and then begin the process of closing you up.

After your baby has been examined, the pediatrician or nurse may hand him to your partner, who can hold him right next to you so you can admire, nuzzle, and kiss him while you’re being stitched up, layer-by-layer.

The Biophysical ultrasound will include.

Fetal position.
Placenta position.
Fetal heart doppler.
Amniotic fluid index.
Rest of the biophysical profile testing which is checking Fetal breathing, movements and muscle tones.

Here you have some pictures of a 40 weeks ultrasound!!

40 week pregnancy and ultrasound

40 week pregnancy and ultrasound

40 week baby ultrasound

40 week pregnancy and ultrasound

40 week baby ultrasound

40 weeks baby ultrasound

40 weeks baby ultrasound

Keep in mind that all these images are sometimes not possible to achieve at 40 weeks, especially if your baby is down within your pelvis.

Tips for You This Week

Try to Stay Relaxed

Of course, you’re excited, anxious and nervous. But it’s important to try to relax as much as you can during the early phase of labor. You’ll need to save your strength for later on. If it’s nighttime, do what you can to get some sleep (when your contractions become more insistent, you won’t be able to). If it’s daytime, keep yourself busy. Cook a few more dishes to add to your freezer stash, fold some baby clothes and do the rest of the laundry so you can come home to an empty hamper.

Perhaps try to mildly exercise.

You can also try taking a walk (or a waddle), which might even kick up the contractions a notch, just don’t stray too far from home, and don’t go anywhere without a cell phone. Eat a light snack if you’re hungry, but avoid fatty foods and don’t overeat. Don’t worry about obsessively timing contractions at this point (you’ll just get bored and frustrated), but do check periodically to see whether they’re getting closer together.

And finally…

Make sure that you have Hospital bag ready to go and Nursery ready for the baby arrival.

In conclusion

Here you have the most important information about your 40-week Pregnancy.
I hope this information was helpful to you.
If you like this post, keep sharing to other mommies.
An stay tuned for more helpful posts like this one, any questions feel free to comment below.

XO Zadi.

Disclaimer: Due to HIPPA regulations all patient information is protected on this site. The majority of the Ultrasound images are my own. The information provided on this blog is designed to be used for educational purposes and is made with the best of my knowledge. Therefore, this post is not intended to diagnose or treat any medical condition. For diagnosis or treatments consult your doctor. The author is not responsible or liable for any mistreated pathologies.






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Ultrasound sonographer for many years and mommy of 2 boys, I love my kids therefore I love what I do, help other women to achieve a healthy and successful pregnancy is my goal.

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