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The last 3 months of pregnancy – the third trimester

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During this last 3 months of pregnancy, the third trimester, you may be worried or anxious about labour and wish for the time before the birth to go quickly.

You will probably gain about 5 kilograms during this stage. Much of this weight will be from your baby, but you will also gain extra weight from the amniotic fluid, the placenta, your breasts, blood and your uterus.

You will need to have more frequent antenatal checkups during this time - about 4 weekly until 36 weeks, then 2 weekly after that. Your doctor or midwife will continue to monitor your progress to make sure all is going well.

  • Problems which can make your life uncomfortable at this stage may include back pain, difficulty getting comfortable enough to sleep, and pressure on your lungs from the baby.
  • You may get more Braxton Hicks contractions - tightenings of the muscles of the uterus. They last about half a minute, are irregular and not painful. They are not a sign of labour starting.
  • You will probably begin to feel quite tired.

Try to relax and get all the rest you can - your baby's arrival is not far away.

More information

There is more detailed information about the development of a baby on the Raising Children Network site

There is also a section for fathers on the Raising Children Network site

Pregnancy, birth and baby website

Week 29

  • You
    You probably feel as though the baby is pushing against all your internal organs. This is because your uterus is pushing up against your diaphragm, stomach, liver and intestines.

    Some women stop work around this time because they start to feel more tired.
  • Your baby
    Your baby is now about one third of its birth size.

Week 30

  • You
    Pregnancy hormones have been softening your ligaments. The combination of this and your baby's increasing weight can cause problems with backache. It's therefore really important to maintain good posture when you are standing or sitting. Try putting a cushion behind the small of your back when you are sitting. Take care when lifting, and it can be better to avoid wearing high heels from now on.

  • Your baby
    Your baby's eyes are learning how to focus. Even if you don't notice regular Braxton Hicks contractions, your baby is becoming very aware of them.

Week 31

  • You
    You may start to feel breathless at times because the baby is pushing up against your lungs, particularly when you are sitting. This feeling is normal and does not mean that you or your baby is getting less oxygen.
     
  • Your baby
    Your baby's lungs are maturing, but they still need to develop surfactant, a substance that allows your baby to breathe after it is born.

Week 32

  • You
    Many babies will begin to settle into a head-down position in the uterus. This is because the top part of the uterus is larger and allows more room for the biggest part of the baby, which is baby’s bottom and bent up legs. At this stage the baby still has plenty of room to move around in the uterus and the position is not important.
     
  • Your baby
    Your baby now weighs about 1.8 kg, and is about 41 cm long.

Week 33

  • You
    You will begin to feel your baby's movements more as prods and kicks and you may even be able to tell the difference between a foot, knee or your baby's bottom.
     
  • Your baby
    Your baby is now beginning to form fat reserves under the skin, and is growing quickly.

Week 34

  • You
    At your checkups, the doctor or midwife will check on the growth of your baby and ask if your baby is moving or kicking regularly.

    It is important that you rest as much as you can with your feet elevated, especially if you have swelling in your feet or ankles. From now on you should avoid lying flat on your back because in this position the weight of the baby and the uterus place pressure on major blood vessels and may cause you to feel faint.
     
  • Your baby
    Your baby can now tell the difference between dark and light and their skin is becoming smoother and less wrinkled.


    (Click on image to enlarge)

Week 35

  • You
    You may find that you need to urinate (pass water) more often as your baby's head is pushing on your bladder. When you laugh, sneeze or cough, you may lose a small amount of urine. It is important that you do pelvic floor tightening exercises, as these will help you control your bladder more quickly after the baby is born. If you don’t know how to do pelvic floor exercises, your doctor or midwife can teach you.

    Physiotherapists also have a range of exercises for the pelvic floor. If you go to antenatal education classes these will be explained. It is important to do these exercises for the rest of your life. To find out more see the topic Pelvic floor exercises.
     
  • Your baby
    Measuring about 44 cm in length and weighing around 2.5 kg, your baby is now almost fully developed.

Week 36

  • You
    Your baby’s head may begin to move down or engage into your pelvis about this time. You will find that breathing is easier once your baby’s head is engaged, as your baby’s bottom will no longer be pressing up against your lungs.

    Around 4 in every 100 babies remain in the breech position at the end of the pregnancy. A breech position means the baby has the bottom down instead of the head. If your baby stays in this position some doctors may attempt to turn the baby to a head down position for the birth. If the baby cannot be turned, your doctor may recommend that the birth be by acCaesarean section. Have a look at the topic 'Breech position and delivery'.
     
  • Your baby
    Your baby is almost fully mature now.

Week 37

  • You
    Your pattern of sleep may be troubled and you may find it hard to get comfortable in bed. It might be helpful to use pillows between your knees and to support your abdomen as you lie on your side.
     
  • Your baby
    Your baby is now about 50 cm long, and may practise breathing movements, but of course there is no air in their lungs yet.


    (Click on image to enlarge)

Week 38

  • You
    Your baby may be moving a little less now as there is less space to move and instead of whole body movements, you may only notice jabs from their foot or knee. You may also feel a sensation inside your vagina as your baby's head is moving against your pelvic floor muscles.
     
  • Your baby
    Your baby may be putting on 100 g a week at this stage, and on average now weighs around 2.9 kilograms.

Week 39

  • You
    Your cervix is softening in readiness for labour. You may also be experiencing quite strong Braxton Hicks contractions. You may be feeling very heavy and weary and just waiting for the baby to hurry up and arrive.
     
  • Your baby
    Your baby's sucking and breathing reflexes are now well established, and your baby is fully ready for life in the outside world.

Week 40

  • You
    Although your due date has arrived remember that your labour may begin one or two weeks either side of this date.
     
  • Your baby
    By full-term, most babies weigh about 2.7 to 3.5 kg - although full-term babies can weight anything from about 2.5 to 5 kg. They will measure 35 to 38 cm from crown to rump and 44 to 55 cm from the baby's head to its toes. There can be wide variation in the measurements.
     

The birth

Have a look at the group of topics in The birth section of this site.

Resources

The Raising Children Network, a comprehensive Australian resource for expectant parents and parenting newborns to teens, has developed a resource for fathers to be which provides information on a range of issues related to pregnancy and fatherhood.
http://raisingchildren.net.au/dads_guide_pregnancy/dads_guide_to_pregnancy.html  

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The information on this site should not be used as an alternative to professional care. If you have a particular problem, see your doctor or midwife.

 

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