Fetus Growth & Pregnancy Symptoms Week by Week

Third Trimester

Published : 07/05/2024

Last updated: 11/05/2024

The third trimester is from weeks 27-40 or months 7-9. The little one’s growth picks up the pace and gains weight rapidly. Their brain is expected to triple in weight, eyes will open, bones shall harden, circulatory systems will finish developing and they will get ready to be welcomed to the world!


For mothers, however this trimester can be challenging both physically and emotionally. Symptoms starting with backaches, hemorrhoids, varicose veins, shortness of breath, heartburn and difficulty controlling your bladder are mostly the new developments but some mothers observe fewer symptoms.


Here is a brief overview of the third trimester summing up your baby’s growth and what else to expect. As always all notes and comparisons are kept simple for ease of understanding..


Pregnancy Week 27

The third trimester starts with the little one being the size of a cauliflower and an almost similar facial appearance they will have at birth.


Around this time the baby will be able to open their eyes and perceive light and dark from within the womb.


For mothers you might start noticing extra facial and body hair, very few have the restless legs syndrome, pelvic pain, and swelling of feets.

Pregnancy Week 28

At 28 weeks your fetus is about the size of a large eggplant and has grown considerably nearing to the 1kg mark.

The little one’s sense of hearing, touch and smell are functional and developed.

You might feel leg cramps, observe hemorrhoids (blood in your stool, caused by light bleeding in the pelvic area) and pregnancy rashes.

Pregnancy Week 29

At 29 weeks your baby is about the size of a butternut squash.

You might feel stronger hiccups around this time, this is totally normal. and may have a role in lung maturation. Also your babies bones are getting stronger so it is recommended to not miss your daily dosage of milk.

Make sure to consume enough Iron to avoid anemia during pregnancy.

Pregnancy Week 30

About the size of a large cabbage your baby is growing like a champ at week 30!


You may start to notice that your baby is getting used to a sleep cycle.


You might start noticing that your belly button has changed, brown discharge from your vagina and most definitely heavy mood swings.

Pregnancy Week 31

At 31 weeks your baby is the size of a coconut and they expected to gain steady weight every eek from here onwards.

The little one is starting to get fat deposits under their skin. Their brain is also growing rapidly around this time.

You might start to feel uterus muscles tightening now and then, these contractions are called Braxton Hicks contractions.

Pregnancy Week 32

At 32 weeks your baby is long as a stalk of asparagus and quickly filling up the space on your uterus.

The baby is preparing to get into ideal position for delivery  also if your baby is born around this time it is called moderately preterm birth, and often need care on the NICU, but are unlikely to have lasting problems.

You might start to experience sharp pains in the pelvic area, also swollen face and hands and swollen/ varicose veins.

Pregnancy Week 33

At 33 weeks your baby is the size of a medium pineapple and has almost developed their full immune system.

Your baby’s skin is losing its wrinkly transparent red look – it’s becoming soft and smooth!

You might start to notice appetite changes and feel less hungry

Pregnancy Week 34

Your baby is approximately the size of a cantaloupe.

Bones are fully developed, limbs become chubby and the lil one should increase movement.

You might start feeling increased pelvic pain and lower-back pain.

Pregnancy Week 35

Your little one is about the size of a honey dew lemon. 

The baby will slowly start to get into delivery position with head down and feet pushing into the diaphragm.

You’ll start feeling clumsy, get a lot of headaches and acidity.

Pregnancy Week 36

At 36 weeks your baby is about the size of a romaine lettuce.

Your baby is getting into position or is in position of birth. If your delivery happens this week it’s considered late preterm birth and will have the same possibility of being as healthy as a full-term infant.

You might feel contractions along with lower back pain, contractions might also come at regular intervals. You might also notice vaginal discharge or spotting or other signs of premature labor.

Pregnancy Week 37

At 37 weeks your baby is roughly the size of a stalk of large Swiss chard.


Your baby is continuing to gain weight by adding fat under their skin.


You might notice Braxton Hicks contractions, leaking breasts and lower back pain.

Pregnancy Week 38

About the length of leek around 38 weeks your baby is shedding their first body hair (fur-like)- lanugo.

Your baby is ready for their first pictures.

You will be at the peak of your nesting instinct – fueled with energy you will find yourself motivated to set up your baby gear, clean the nursery and start stalking foods, this is completely natural.

Pregnancy Week 39

AT 39 weeks the baby is about the size of a medium sized pumpkin and is full-term.


Your baby’s lanugo and vernix (white creamy substance) will have completely disappeared. 


Your doctor might check for changes in your cervix for example softening, effacing and dilating. You might also notice water break at any moment around this time.

Pregnancy Week 40

AT 40 weeks your baby is about the size of a small-medium watermelon and most often this is the final week of pregnancy.


You have done it! Sometime around this week you are about to meet and greet your tiny little human! Congratulations! 

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