40 Weeks Pregnant – Belly Size, Baby Development, Symptoms & More

Medically Reviewed By
Dr. Deepinder Kaur (Gynaecologist)
Expert Validated

Congratulations on coming this far because week 40 means you and your baby are officially about to meet each other really soon! This is an incredible milestone, as being 40 weeks pregnant marks the final stretch of your pregnancy journey. Many pregnant women take precautionary steps and prepare for the arrival of the baby by reading up on various pregnancy-related materials, packing their hospital bags, and ensuring their home is baby-ready. It’s also a good time to rest and stay hydrated, as labour could start at any moment. We’ve got you covered with helpful tips to ease your transition into parenthood!

ADVERTISEMENT

Your Baby’s Growth During Pregnancy – Week 40

Your baby is making remarkable progress as she develops in the womb. Some of these developments include:

Your Baby's Growth During Pregnancy - Week 40

ADVERTISEMENT


ADVERTISEMENT
  • Layering up on fat: 15% of your baby’s body will be made up of fat that helps the little one in regulating her body temperature.
  • Nails and hair continue to grow: At 40 weeks, your baby’s nails and hair are still growing and will be more defined.
  • Lung adaptability: The lungs are almost developed for breathing the air outside.
  • Stocking up on antibodies: The placenta still gives the baby all the antibodies that she needs to ward off infections for the initial 6 months of her life.
  • Eyesight develops: Baby’s eyesight will be blurry and can focus only on objects that are an inch away.

Apart from these developments, there are other significant changes in her body that can be observed. For example, to ensure smooth passage for your baby through the birth canal, the bones in the skull will not be completely fused.

Your baby’s body can now successfully break down bilirubin by moving across the placenta where it gets flushed out with the other waste products. Once the baby is born and the umbilical cord is cut, her body will have to get rid of the bilirubin on its own. This will normally take a few days. Sometimes, it gets built up in the baby’s body, and hence the baby may contract jaundice. This can be taken care of by exposing her to light.

ADVERTISEMENT

What Is the Baby’s Size?

At 40 weeks pregnant, the baby’s size would be between 2.7 kg to 4 kg by weight and will measure between 19 inches to 22 inches long in height (though a lot of babies who are born smaller or bigger have grown up to be healthy). Your baby will be the size of a watermelon at this time.

Common Body Changes

Your body changes during pregnancy to accommodate and nurture the growing foetus. It is important to know that it is not necessary that your water will rupture before the onset of labour. In fact, very few women experience this. Even if your membrane ruptures, it will be a slow trickle or leak or even a small gush.

ADVERTISEMENT

Symptoms of Pregnancy at Week 40

Pregnant women may experience the following symptoms:

ADVERTISEMENT

1. Leg cramps

The baby at this stage will drop lower in the pelvis, thereby increasing the discomfort in the pelvic region. This is very common at 40 weeks.

ADVERTISEMENT

2. Insomnia

It is okay if you can’t sleep as anxiety can keep you up at night. You may want to indulge in some relaxing activities like reading a book or writing a journal. Plenty of rest is advised.

3. Fatigue

Since you can’t sleep properly, you are bound to feel tired. So, make sure you have some peace and quiet time to help you relax.

ADVERTISEMENT

4. Contractions

Those false contractions that you’ve probably been experiencing all this while (Braxton-Hicks) may actually ‘not be so false’ anymore. Time your contractions to analyse how far apart they actually are. In case the time difference between two contractions is very less, you may have actually reached an early stage of labour.

ADVERTISEMENT

Contractions

What Are the Signs of Labour?

There might be no signs of labour at 40 weeks. However, you can expect these signs to arrive soon:

  • Frequent, rapid contractions: Once you start having contractions that make you uncomfortable or keep coming at regular intervals, you must go to the doctor.
  • Water leak/ break: You can check to see if there is a leak of amniotic fluid. This will mean that the water has broken or ruptured. You can easily distinguish between amniotic fluid and normal discharge. The flow of amniotic fluid will not stop, unlike a regular discharge.

Inducing Labour at 40 Weeks

There are multiple ways to do this:

ADVERTISEMENT

1. Membrane stripping

The doctor will put his or her gloved finger inside the cervix and sweep the membrane. This helps in producing prostaglandins that help to soften the cervix and induce labour. At this time, you may feel intense cramping and a little bit of bleeding. This procedure might be a little uncomfortable.

ADVERTISEMENT

2. Dilating or ripening of the cervix

The doctor might induce labour with the help of certain medications if the cervix isn’t ready for labour. The synthetic medication called prostaglandins will induce labour, and can be taken orally or inserted into the vagina.

3. Rupturing the amniotic sac

The amniotic sac can be ruptured to start labour. This is called amniotomy. Here, the doctor will break or rupture the amniotic sac using a thin plastic hook. This is done only when the head of the baby has moved down, or for a partially dilated cervix. For some women, the labour can happen within a few hours of breaking the water. However, it should be kept in mind that this varies for every woman.

ADVERTISEMENT

4. Pitocin

These are synthetic hormones that can induce labour, or make the contractions stronger.

Belly at 40 Weeks of Pregnancy

Two weeks after the due date, if you are still pregnant, then it is officially post-term. 12% to 13% of women have a post-term pregnancy. The good news is that the baby must come at some point, and the bad news is that it could take another two weeks at most.

ADVERTISEMENT

40 Weeks Ultrasound

40 weeks pregnant ultrasound of the baby will allow the doctors to know how developed the baby’s lungs are. A non-stress test will be done to monitor the baby’s movements and see how her heart rate holds up during contractions. If the test results indicate that the baby will do better outside than inside the uterus, then labour can be induced.

ADVERTISEMENT

What to Eat

Below is a list of 40th-week pregnancy food items that a mother can consume during this period:

  • Toast: It needs to be kept bland, but consume enough that it gives plenty of energy without straining the digestive system.
  • Pasta: Bland pasta is advisable, as it provides a good carb-load for the strenuous exertion that happens during labour.
  • Jell-O or Applesauce: These are easy to consume, and act as energy boosters.
  • Sorbet or Popsicle: This helps to keep oneself hydrated and provides jolts of little energy. If they are made up of fruits, then these will provide vitamins as well.

Pasta

Tips & Care

Below are a few tips that a mother can follow to keep herself comfortable.

Dos

  • Stimulating the nipple: Nipple stimulation releases the hormone oxytocin, which causes contraction of the uterus. But this must be done only if the doctor approves of it.
  • Walks: Walking helps to induce labour, by allowing the baby to move further down the birth canal. This also brings down the discomfort that women feel when they are experiencing contractions.
  • Spicy food: It is not proven that having spicy food induces labour, but you can try having food that has lots of garlic and cumin to trigger labour.
  • Sexual intercourse: This helps to induce labour, and at the same time makes your partner and you feel closer to one another.

Tips & Care at 40 weeks pregnantDon’ts

  • Caffeine: Apart from aggravating insomnia, coffee has been known to increase the chances of diabetes for the child.
  • Smoking: Even if you don’t smoke, being exposed to second-hand smoking can bring about respiratory disease in the unborn child.

Don'ts at 40 week pregnant

What You Need to Shop

A few things that a mother needs to have in hand before her bundle of joy gets out are:

ADVERTISEMENT

ADVERTISEMENT

FAQs

1. Can being 40 weeks pregnant increase the chances of a larger baby?

Yes, being forty weeks pregnant can slightly increase the chances of having a larger baby as the baby continues to gain weight in the final weeks of pregnancy. Regular check-ups with your doctor can help monitor the baby’s growth and ensure a safe delivery.

ADVERTISEMENT

2. Is it normal to experience a decrease in fetal movement at 40 weeks?

While some decrease in fetal movement can be normal due to reduced space in the uterus, significant changes should be reported to your doctor immediately. Monitoring kick counts can help you track your baby’s activity levels.

3. Can I refuse an induction at 40 weeks if I feel fine?

Yes, you can discuss your concerns with your healthcare provider and choose to wait if there are no medical complications. Many women prefer to let labour start naturally unless there’s a risk to the baby or mother.

ADVERTISEMENT

This was all about the 40th week of pregnancy. With the baby ready to come out anytime now, watch out for all the signs that may point to the start of labour. Also, make adequate arrangements so that when the time comes, you can head to the hospital without any difficulty.

ADVERTISEMENT

ADVERTISEMENT

References/Resources:

1. Week 40; NHS; https://www.nhs.uk/start-for-life/pregnancy/week-by-week-guide-to-pregnancy/3rd-trimester/week-40/

2. 40 Weeks Pregnant; American Pregnancy Association; https://americanpregnancy.org/healthy-pregnancy/week-by-week/40-weeks-pregnant/

3. FAQs: How to Tell When Labor Begins; American College of Obstetricians and Gynecologists; https://www.acog.org/womens-health/faqs/How-to-Tell-When-Labor-Begins

4. FAQs; Labor Induction; American College of Obstetricians and Gynecologists; https://www.acog.org/womens-health/faqs/Labor-Induction

5. Labor and birth; OASH: Office on Women’s Health; https://womenshealth.gov/pregnancy/childbirth-and-beyond/labor-and-birth

6. Overdue pregnancy: What to do when baby’s overdue; Mayo Clinic; https://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/in-depth/overdue-pregnancy/art-20048287

7. 10 Signs Labor May Be Beginning; Cleveland Clinic; https://health.clevelandclinic.org/signs-that-labor-is-24-to-48-hours-away

Previous Week: 39 Weeks Pregnant

Next Week: 41 Weeks Pregnant

Was This Article Helpful?

Parenting is a huge responsibility, for you as a caregiver, but also for us as a parenting content platform. We understand that and take our responsibility of creating credible content seriously. FirstCry Parenting articles are written and published only after extensive research using factually sound references to deliver quality content that is accurate, validated by experts, and completely reliable. To understand how we go about creating content that is credible, read our editorial policy here.

  • Author
  • Expert Reviewer
About the Author
Romita P

Dr. Deepinder Kaur About the Expert
Dr. Deepinder Kaur
(Gynaecologist)

ADVERTISEMENT

Latest Posts

ADVERTISEMENT
FirstCry Logo
Ratings
Download the FirstCry App and get access to
15000+
Articles
Ad Free
Experience
Personalised
Content
QR Code
Scan the QR code and download the app