Week 40 of pregnancy
Updated 25 Oct 2026
Your baby this week
About the size of a large pumpkin
Source: Vinmec – Bảng cân nặng và chiều dài thai nhi theo tiêu chuẩn của WHO
Your baby's development
About 30% of pregnancies go past 40 weeks. Some mums carry on until 41 weeks. You don't need to worry too much because the week of pregnancy is only an estimate and can be off a little. Only a pregnancy beyond 42 weeks is considered overdue (post-term), and at that point your doctor will choose a suitable way to help induce labour.
Your baby is 48 - 56 cm long and weighs around 3.2 - 4.1 kg. Your baby doesn't change much from previous weeks because they have reached full development. Your baby's skin has shed most of the vernix (the waxy outer coating).
So our little angel is pretty well prepared to turn their parents' world upside down! Let's see – we'll definitely need nerves of steel to face this super-cute bundle of trouble.
Your body
Now, these symptoms are about to start saying goodbye to you:
- You may feel Braxton-Hicks contractions.
- Baby's movements: curling up, kicking, punching.
- Cramps, trouble sleeping and loose stools may happen.
- You may go into labour: tummy pain coming in waves, vaginal discharge, vaginal bleeding, or your waters breaking.
Advice for you
Talk to your doctor at this point if you haven't given birth yet, and keep track of your baby's movements regularly. You should also recognise the signs of labour so you can go to hospital. Don't worry too much or use methods not proven by science to bring on labour.
It's best if your partner and family are close by at this time to help when needed.
Momby wishes you and your baby a safe and healthy birth. And welcome to our world, little one, with love and so much more.
Watch the video for this article
Signs that need a doctor now
If you notice any of the signs below, please go to the nearest health facility to be checked by a doctor.
Vaginal bleeding in pregnancy
This sign needs to be checked by a doctor. Please go to the nearest health facility now. If the bleeding is heavy or comes with severe pain or faintness, call the emergency number 115.
Source: Bệnh viện Đa khoa Tâm Anh – Các dấu hiệu nguy hiểm trong thai kỳ
Convulsions (fits)
A convulsion in pregnancy is an emergency. Family members should call 115 at once, lay the mother on her side in a safe place and get her to the nearest hospital.
Source: Bệnh viện Đa khoa Tâm Anh – Các dấu hiệu nguy hiểm trong thai kỳ
Fever in pregnancy
A temperature above 38°C counts as a fever. Please go to a health facility so a doctor can find the cause and advise on safe ways to bring it down; do not take medicine on your own.
Source: Bệnh viện Đa khoa Tâm Anh – Các dấu hiệu nguy hiểm trong thai kỳ
Leaking fluid or waters breaking
Fluid leaking from the vagina may mean the waters are leaking or have broken and needs to be checked by a doctor. Please go to a health facility soon, lying with your head low while travelling.
Source: Bệnh viện Đa khoa Tâm Anh – Các dấu hiệu nguy hiểm trong thai kỳ
Severe headache, blurred vision, sudden swelling
Headache with blurred vision, or sudden swelling of the face, hands or eyelids, can be a sign of high blood pressure in pregnancy or pre-eclampsia. This sign needs to be checked by a doctor. Please go to the nearest health facility now.
Source: Bệnh viện Đa khoa Tâm Anh – Các dấu hiệu nguy hiểm trong thai kỳ
Reduced or no fetal movement
A clear drop in the baby's movements, or no movement, needs to be checked by a doctor. Please go to the nearest health facility now rather than waiting until tomorrow.
Source: Bệnh viện Đa khoa Tâm Anh – Các dấu hiệu nguy hiểm trong thai kỳ
Severe or worsening abdominal pain
Abdominal pain that keeps getting worse, does not ease, or is severe needs to be checked by a doctor. Please go to the nearest health facility now. If the pain is severe with sweating, faintness or bleeding, call 115.
Source: Bệnh viện Đa khoa Tâm Anh – Các dấu hiệu nguy hiểm trong thai kỳ
Sources
Content advised by our doctors.
- ACOG (accessed 22 Oct 2026)
- Vinmec (accessed 22 Oct 2026)
- NHS (accessed 22 Oct 2026)
- Source for fetal size: Vinmec – Bảng cân nặng và chiều dài thai nhi theo tiêu chuẩn của WHO
- Source for the signs that need a doctor: Bệnh viện Đa khoa Tâm Anh – Các dấu hiệu nguy hiểm trong thai kỳ
This article helps you understand and prepare. It does not replace a check-up. For an answer about your own situation, please ask the doctor who is caring for you.