Track your pregnancy week-by-week

Pregnancy week by week

40 Weeks Pregnant

Length of baby: 51.3cm
Weight of baby: 3.4kg
At week 40, your baby is ready to come out to meet the world!


Congratulations you are due this week!

After weeks of waiting, the big day has finally arrived! Ensure that you have everything ready to go at the drop of a hat, and that you have babyproofed your home.

You should also put a waterproof cover over your bed in the event your water breaks in the middle of the night.

This week, you will find yourself wondering when your water is going to break. On top of that, you’ll have many questions about every feeling that you’re experiencing at your pelvis area.

Don’t stress it, because your baby will arrive when he or she is ready.

Though this week you are officially at the end of your pregnancy, some pregnancies do last more than 40 weeks.

That is because some women ovulate later than expected and should you calculate your due date from the day of your last period, you’ll find that you’re not at all as late as you think it be. 

However even with reliable calculations, some women have pregnancies past 40 weeks for no apparent reason.



How big is baby at 40 weeks? Your baby measures about 51.3cm.

The current weight of your baby is about 3.4kilograms, and is as heavy as a watermelon.



This is the weight gain that you must achieve this week.

Underweight(BMI <18.5)  0.44kg to 0.58kg
Normal weight(BMI 18.5 to 24.9)0.39kg to 0.50kg
Overweight(BMI 25 to 29.9) 0.23kg to 0.33kg
Obese(BMI ≥ 30) 0.16kg to 0.25kg



Other than the symptoms that you have already been experiencing, you should be watching out for signs of labour.

Being 40 weeks pregnant, here are some signs and symptom that your body might be experiencing:

  • Braxton Hicks Contractions. The contractions that have become more frequent will soon become labour contractions, which means you will have the contractions with short intervals for an extended period of time.
  • Lack of sleep. By now you would find yourself exhausted and facing a lack of sleep due to the bulging belly. Do take every chance you get to rest and keep your energy levels up.
  • Leg Cramps. With the baby now at full term, you will be carrying that extra weight around. This could cause you to develop leg cramps, so do rest and stretch if you experience the cramps.
  • Nervousness. You might stress over your baby’s arrival. He or she will arrive when he or she is ready, keep your stress levels down with some meditation.



Here are some 40 weeks pregnant signs of going into labour:

  • Contractions. If you are having contractions, remember to keep track of your contractions. It usually begins with contractions within five minutes apart for at least an hour. Thereafter when you get into active labour where contractions are stronger, you should be in the hospital. 
  • Loose Stools. As your body gets ready for childbirth, it will release chemicals to cause the uterus to contract and the cervix to dilate. These chemicals will also cause you to get loose stools or even diarrhoea.
  • Water breaking. If you feel water leaking from your vagina in a slow trickle or even a gush, that is probably amniotic fluid and you will go into labour soon. If your water has broken, you should call your doctor and get to the hospital.
  • Vaginal discharge. When you pass out your mucus plug, which is a bloody thick red/pink/brown mucus-like lump, this will mean your cervix is starting to dilate. This could come loose up to a few days before labour begins.


Remember to put a waterproof mattress cover over your sleeping area in the event your water breaks in the middle of the night.



This is the week! You might be wondering, how should you induce labour naturally at 40 weeks pregnant? 

Here are some options for you to induce labour:

  • Take a walk. Walking allows your hips to sway from side to side, which could get your baby into position. On top of that, gravity could help bring the baby down to the pelvis region. Even if you don’t go into labour by walking, you’re still getting some exercise in! It’s a win-win situation.  
  • Nipple stimulation. Massaging the nipples is a way to induce labour. The stimulation makes the body release oxytocin, which causes contractions, which could develop into labour. However, don’t try this technique at home because it may over stimulate your uterus and your baby will need to be monitored.
  • Having Sex. Sex is the most well known natural method to induce labour. The female orgasm has been known to open the cervix up to two centimetres, while semen has prostaglandins, a hormone which is involved in the start of labour. On top of that, having sex also releases oxytocin, which causes contractions that can develop into labour. 



At week 40, your doctor may help to induce your labour if there a threat to the Mother or the Baby. Whether or not this is necessary depends on how the baby is doing in the womb. If the baby is perfectly healthy, your doctor will ask you to wait it out. 

However if there is a need for a medical induction, here is how your Doctor can medically induce you into labour at 40 weeks pregnant: 

  • Sweeping Membranes. This method involves your doctor sweeping their finger (with gloves of course) between the thin membranes of the amniotic sac found in your uterus. This will increase prostaglandin production, which can cause the contraction of your uterus, thus inducing labour. 

  • Rupturing Membranes. Your doctor intentionally breaks your water to induce labour. It is done using a small hook to break the amniotic sac that holds your baby. 

  • Foley Catheter Induction. Your doctor may insert a Foley catheter into your vagina and inflate the catheter to stretch your cervix to induce labour. 

  • Pitocin Induction. You will be given an IV drip of Pitocin which acts the hormone oxytocin to induce labour. Your doctor can adjust the amount you need according to the progress of your labour. 

  • Ripening the cervix. If your cervix is not dilated yet, your doctor will admit you to the hospital and administer a medication that contains synthetic prostaglandins, which will be inserted into your vagina. This can also be given in an oral form known as misoprostol. These help to ripen your cervix and stimulate contractions.



Your baby’s skull is not fused together, and this allows some overlap so the little one is able to better fit through the birth canal during labour.

This is also the reason why some babies look like they have “sharp” heads after birth. Rest assured that this is normal and it is only temporary.

At this stage, you are still providing the little one with antibodies needed to fight off infections once he or she meets the outside world.

Breastfeeding (and colostrum, which is produced for up to five days after birth) once the little one is born will also help boost the immune system further.

This week you may have a biophysical profile (BPP), where your doctor will perform an ultrasound to monitor the level of amniotic fluid because it is a good reflection of how well the placenta is supporting the baby.

This is combined with a non-stress test, where the baby’s movements, breathing and heart rate are monitored.

If the results indicate that it is safer for the baby to be delivered, your doctor may order a medical induction.However, if test reveals that everything is fine, sorry but the waiting game resumes. 



Reminders for the week:

  • Try to induce labour naturally
  • Sit back, relax and read a book or watch a drama 
  • Schedule next week’s prenatal visit (if you have not given birth)