The third trimester overview

The third trimester overview

What to expect in your third trimester of prenancy

Congratulations, you have reached the homestretch. The third trimester lasts from week 28 to week 40, which is normally the time of birth. You will now start to see your doctor on a more regular basis as monitoring during this stage is vital. You are likely to be going to the toilet more and more now and may even have difficulty breathing as the baby presses on your diaphragm. The baby is getting bigger and bigger, resulting it in pushing on some of your organs, usually your lungs and bladder. These signs are normal and healthy.

Third trimester tests and risks

In seeing your doctor more frequently now, he/she is likely to conduct tests on and assess the following:

  • Urine tests for protein
  • Blood pressure tests
  • Measurement of uterine growth
  • Checking legs and hands for swelling
  • Checking the baby’s position in the cervix ensuring that it is correct for birth

You may also be screened for Group B streptococcus bacteria. This involves taking a swab sample from the vaginal region and sending this to a lab to be tested. If this bacterium is found it is a severe threat to the baby as it is passed through the vagina during delivery. If you do have this bacterium, your doctor will prescribe antibiotics to get rid of it.

Your doctor will also inform you about travel restrictions and advise that you stay close to him/her or your chosen midwife as you get closer to your due date.

Cruise ships and airlines do not typically allow women that are over 28 weeks pregnant to travel.

It is best that during this time you know about the stages of labour and what the options for delivery are. Ask your doctor about any questions you may have in order for you to feel comfortable about the birth of your baby.

Third trimester emotional and physical changes

The discomforts that you felt in the second trimester are likely to worsen in the third trimester.

Other changes are likely to be any of the following:

  • Haemorrhoids also known as 'piles' may start to develop
  • Your ankles, face and fingers may experience swelling
  • Breasts may be tender and may also leak a milky discharge
  • Your belly button can start to protrude
  • You may start to experience contractions which can be real or false labour signs (these are referred to as Braxton Hicks)
  • Your baby will start to drop or move lower in the abdomen
  • You may also have heartburn, shortness of breath and difficulty sleeping as you feel uncomfortable

Third trimester baby growth as due date gets closer

Your cervix starts to thin and become softer as your due date approaches, this process is known as effacement and aids in your cervix opening for childbirth. Your doctor will monitor your internal changes with regular exams and testing.

Third trimester baby growth at 32 weeks

Your baby will continue to develop in the following ways:

  • Your baby’s bones are fully formed but soft
  • The lanugo hair layer will fall off
  • Your baby grows rapidly
  • The body of your baby will start storing important minerals such as calcium and iron
  • Your baby’s eyes can open and close
  • The lungs, not being fully formed, still start to practise the breathing motion
  • Kicking and movement is increasing

Third trimester baby growth at 36 weeks

Your due date is now fast-approaching, and with this, your baby is developing in the following ways:

  • The baby’s body fat is increasing
  • Your baby, now being bigger, will not be able to move as much inside of you, the movements are often more rigid, but you will still feel them
  • The vernix layer of waxy coating is now thickening
  • Your baby is about 40 to 48cm long

Third trimester baby growth at 37 to 40 weeks

This is it. All the waiting, sleepless nights and researching is going to soon be worth it. In the final stages of your pregnancy your baby is undergoing the following changes:

  • Your baby has now fully grown
  • Your baby’s organs have developed fully and can function on their own
  • If all goes according to plan, your baby’s head will now move to the head-down position for the birth
  • Your baby is about 48 to 53cm long

Keep in mind that all babies are born with different weights and sizes. Your doctor will be able to inform you about what a healthy size and weight is.

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