• Penni from Up Up n Away

Pregnancy : 3rd Trimester

Updated: Feb 5

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Week 27


This is the start of the third trimester. Some women find they want or need to start taking things easier around now, if they can. Your weight may increase but remember, that you need not ‘eat for two’. The quality of food of the food is more important than the quantity. Because of the weight women at different rates and times, you should talk with your doctor or midwife about the optimal amount of weight gain during your pregnancy. Your health professional might check your weight at pregnancy visits.

Whooping cough immunisation

Whooping cough is a dangerous illness for babies, and very contagious. To assist protecting your baby from whooping cough, recommendations are that you have a whooping cough immunisation between 20 and 32 weeks of pregnancy. In Australia, the immunisation for it is free for all pregnant women during their third trimester. Your GP or midwife can set up the appointment for you.


Breastfeeding your baby is highly recommended by health authorities and experts. Having a knowledge about breastfeeding before your baby is born can be really helpful. Reputable, current articles on breastmilk and breastfeeding attachment techniques are a good place to start.

Or for more information and support, you can call the Australian Breastfeeding Association on 1800 686 268. Also contact with your doctor or midwife if you have concerns or questions about feeding. Additional knowledge about breastfeeding can be attained via your local child or family health nurse.

Your Baby

  • Your baby is about 24 cm long from head to bottom, and weighs about 920 gm.

  • Your baby can open its eyes.

  • Your baby’s brain is starting to take more shape.

  • Your baby should be putting on lots of weight over the next month or so.

Week 28


Your antenatal appointments are likely to be every 2-3 weeks during weeks 28-36 of your pregnancy.


You might start considering when to stop working. Although some will need to stop earlier or work longer, many women find about 34-36 weeks is ideal.

Depending on your workload as an employee or employer, you might need a certificate from your midwife or doctor to work past a certain point in your pregnancy. There are common health issues that can occur in the third trimester of your pregnancy including :

  • Swelling of the hands and feet. Tip - hydrate, put your feet up, and remove any tight jewellery from your wrists and fingers.

  • Shortness of breath. Note - there is less room for your lungs as your uterus is pushed further up into your ribcage.

  • reflux and heartburn.

  • Pain in your lower back and legs. Tip – tilting your pelvis forward or standing up straight may provide some relief.

  • As your breasts start producing colostrum, leakage may occur.

See your midwife or doctor as soon as possible if you experience any sudden symptoms associated with health issues during pregnancy, or if the severity of the symptoms persist.

Feeling stressed or sad

Utilise your pregnancy check-ups to talk about any concerns or problems at home. Your feelings about what is happening during pregnancy are just as important as physical health problems and symptoms.

If your stress levels are high or your mood is depressive, the health of your or your baby can be affected. Don't hesitate to contact your midwife or doctor to arrange a referral to a mental health professional – for example, a counsellor – or to connect you with the relevant support services deemed beneficial for your situation.

More than mood swings

For both women and men, pregnancy is a life-changing experience where strong and unexpected emotions and issues can surface.

Hormonal changes can affect your level of energy and mood. It is normal that occasionally you or your partner may feel flat or irritable.

If the affects of these emotional changes persist longer than two weeks or start adversely affecting your or your partner’s daily life, this could indicate antenatal depression or other issues.

It is advised that additional appointments with your midwife or doctor should be made to discuss and address these changes. You could also call Lifeline on 131 114, Beyond Blue on 1300 224 636 or PANDA on 1300 726 306.

Your Baby

  • Growing bigger. Your baby will measure about 25 cm from head to bottom, and weigh about 1 kg.

  • Most babies move to the head-down position in time for their birth whereas some babies prefer the breech position at this time ie. head up, bottom down. Most babies move to the head-down position in time for their birth so this need not be cause for great concern right now.

  • The immune system of your baby is further developing.

  • A white, creamy substance called vernix now covers your baby to protect it's skin from amniotic fluid.

  • Your baby’s eyelashes are growing.

  • If you have a boy, his testicles are lowering into his scrotum.

With specialised care, babies born at this stage, though premature, have about a 75-80% rate of survival. The movements of your baby in the womb should now be regular and strong. Call your doctor, midwife or hospital immediately if there is a noticeable change in the number or strength of your baby’s movements at any stage.

Week 29


Lying in bed may become uncomfortable. If so, slightly sit up, lay on your side, and place a pillow underneath your stomach. Alternatively, you can place a pillow between your legs and behind your back for the prevention or ease of back pain.

Now that you’re in your third trimester of pregnancy, the safest recommended sleeping position is on your side. This is because it is known that side sleeping (optimally on the left side) reduces the risk of stillbirth. If you wake during the night on your back it's ok, just roll back on to your side. Immunisation

In Australia, the immunisations required during pregnancy are free all women. Talk to your GP or midwife if you haven’t already had your immunisations against whooping cough or the flu administered.

Staying Active

Physical activity is still important, even though you might be feeling slower and less energetic. It will prepare you for, and assists in recovery, after birth. Check with your midwife or doctor before you start anything new, or if you have any personal concerns about exercise or staying active.

Swimming or aqua exercise is beneficial, because it temporarily takes the weight off legs and feet. Consult with your swimming instructor about swimming style and movements that suitable. There are also yoga and pilates classes available which are designed specifically for pregnant women .

Your Baby

  • Measures about 26 cm from head to bottom, weighing about 1.15 kg.

  • Increases in weight considerably between now and week 38.

  • The functioning of developing organs increases.

  • The bone marrow has started to produce red blood cells.

  • Now practises breathing in and out in a regular rhythm more consistently.

Week 30


As the volume of your blood doubles, at every antenatal visit you attend, your health professional will be checking your blood pressure.

As your baby takes up more and more space inside, heartburn and reflux may also increase, as will the size of your breasts. Your sleep patterns may become more disrupted eg. waking in the night then struggling to fall back asleep. This is tiring but expected so try to rest when you can during the daytime.

Car seats and restraints

Legal requirements for babies 6 months and under travelling in vehicles are that, the approved rear-facing child restraint must be used and also fastened and adjusted properly.

Your local council, ambulance service or a private company may provide the option to hire an approved restraint. Just ask your midwife about options in your local area for if you're not planning on purchasing one, now is a good time to book one for hire. A local fitting station can help you fasten the restraint correctly. It is recommended that your address this as soon as possible in the event your baby is born before the due date.

Your Baby

  • Measures around 27 cm from head to bottom, weighing about 1.3 kg.

  • The fat stores beneath your baby's skin are growing making its appear smoother.

  • The lanugo – The fine hair covering of your baby's body is decreasing. If your baby was born now, quite a lot of lanugo would still be covering its body.

  • May begin to suck their thumbs.

Week 31


By this stage you may have gained some weight and may have noticed the appearance of stretch marks. They are quite common and there’s not a lot you can do about them, but they’ll fade in colour after your baby is born. Creams and other potions don’t work despite what others may claim.

As your centre of gravity shifts the way you walk might change. The body is getting ready for birth with the ligaments around your pelvis are softening and stretching. Switching to flat comfortable shoes may be better than heels for now, not to mention safer.

Birth plans

Now might be a good time to do a birth plan if you’ve been considering one. Birth plans can include things like:

  • who you’d like to be at the birth

  • how you want to manage pain

  • who will cut the cord.

Keep in mind that things don't always go to plan as your baby might have other ideas. Stay flexible and think of the birth plan as a guide. On the day, you may decide what you wanted has changed, so be sure to keep the midwife or doctor updated so they can discuss with you how you’d like your birth environment to be and achieve the birth of your preference.

Your Baby

  • Your baby is about 27.5 cm from head to bottom, and about 1.5 kg.

  • Your baby’s eyes are open, and its pupils can respond to light.

  • Your baby’s brain is developing rapidly, making lots of connections and sending lots of signals.

  • Loud noises nearby might make your baby startle.

Week 32


Due to the pressure of your growing baby and uterus on your lungs you’re almost certainly feeling breathless at times.

If you have belly button piercings, it’s sometimes a good idea to take them out as your belly button may have sticking out or be stretched flat.

Baby basics

Having some basics ready for when baby arrives is a good idea as you’ll feel less like walking around the shops as time goes on. These may include:

  • Somewhere for baby to sleep safely – a cot or bassinet

  • A properly fastened and adjusted, approved, rear-facing child restraint

  • A safe pram or baby carrier

  • Lots of nappies and a nappy bag

  • Wraps – really big cotton or muslin ones are best

  • Clothes for dressing your newborn – most full-term babies can wear size 000, and 100% cotton is best next to baby’s skin

  • Daily care essentials – baby wash (non-soap is best), cream for baby’s bottom, sorbolene cream for dry skin and a thermometer.

Most hospitals and birth classes will help you go through the basics and provide you with lists of items you require. You’ll have your hands full feeding baby, so it’s great if you’ve got a freezer full of some nutritious food to feed yourself and other family members.

Packing your bag

Now is the time to start thinking about packing your bag if you’re planning to give birth in a hospital or birth center. Hospital admission forms, maternity pads, pyjamas and some basics for baby (singlets, socks, tops and bottoms or one-piece suits, large cotton or muslin wraps) are some of the essential items you will need. Old, oversized t-shirts, extra undies, warm socks and lip balm are some things you might want to put in for labour. Other good ideas are easy-open tops for breastfeeding, along with a maternity bra and breast pads.

Extra ultrasound scans

You’re not likely to need any more ultrasound scans after 18-20 weeks if everything’s going smoothly. Your doctor, obstetrician or midwife might suggest extra ultrasound scans if you’re having twins or more, you have a medical condition like gestational diabetes or pre-eclampsia, there are concerns about the growth of the baby, or if you’ve had problems in previous pregnancies.

Sometimes baby is lying in the breech position towards the end of a pregnancy and your health professional might also recommend another scan to check why your baby is in this position and where your placenta is.

Your Baby

Your baby’s weight has almost doubled in the last four weeks. Your baby’s weight will grow faster than its length now:

  • Your baby is about 28 cm long from head to bottom, and weighs about 1.7 kg.

  • Your baby is still putting on fat beneath the skin, looking plumper all the time.

  • Your baby might be head down now. If not, don’t worry. Many babies leave it until the last moment to turn around. Quite a few babies are in the breech position at birth.

  • Your baby’s eyes are a dark grey or blue colour. They’ll change in the weeks after birth, but you won’t know the final colour until about a year after birth.

Week 33


You might be feeling more tired and urinating more often along with more swelling, aches and pains, heartburn and reflux. Rest whenever you can, and accept help whenever people offer it. Enjoy the excitement as the birth date approaches. Signs of labour

Here are some signs of labour, which might start soon:

  • a ‘show’ – this is when the mucus plug that has been sealing your cervix comes away

  • your waters breaking – this could be a slow leak or a big gush. Phone the hospital or let your obstetrician or midwife know

  • more pressure as your baby’s head shifts lower in your uterus and into the pelvis

  • more Braxton Hicks contractions

  • cramping in your lower pelvis, a bit like period pain.

Indications you're in labour are when you feel contractions that last for a minute each, coming at regular intervals (about five minutes apart). ‘Back-up’ for after your baby is born is a good idea. You don’t have to do everything if others are willing to lend a hand. In fact, some people appreciate you telling them exactly what you need. For example, could extended family, friends cook you a meal, drop in for a visit or give you a call? It’s OK to ask for help too.

Your Baby

  • Your baby is about 29 cm from head to bottom, and weighs about 1.9 kg.

  • Your baby is practising sucking and swallowing. These reflexes won’t be fully coordinated until about the end of 34 weeks pregnant.

  • Your baby’s liver is storing iron. These iron stores will help your baby until 4-6 months after birth.

  • Your baby’s lungs are maturing, producing lots of surfactant to help your baby breathe after birth.

  • Your baby’s movements will change as your baby gets bigger. If you’re worried about an increase or decrease in your baby’s movements at any stage, speak with your doctor or midwife.

  • Babies born now have a very good chance of survival, but are still premature. They’ll need to be looked after in an intensive care or special care nursery.

Week 34


As baby’s weight continues to increase you’re probably feeling more and more uncomfortable . Healthy eating and some light exercise might help you feel better. Keep doing your pelvic floor exercises. Putting pillows under your stomach, between your legs and behind your back can help you to feel more comfortable and ease or prevent back pain. Sleeping on your your left side is best when you can. This reduces your risk of stillbirth. If you wake up during the night on your back, just roll over to your side again.

Braxton Hicks contractions may become more noticeable now.

Rh type

To know your Rh type, a blood test is done earlier on in the pregnancy. This can cause serious health problems for your baby if you’re Rh-negative, and your baby turns out to be Rh-positive. Your baby’s blood type won't be known until after birth. You’ll be offered a special injection called Anti-D at your 26-28 week antenatal visit and your 34-36 week visit if you’re Rh-negative.

If you have a bleed during pregnancy you’ll also be offered Anti-D . This reduces the risk of health problems. You’ll be offered another Anti-D injection if your baby is Rh-positive. To do this, blood is collected from your baby’s umbilical cord after birth and the Rh type is checked. Ask your doctor or midwife for more information.


15% of pregnant women can develop a serious condition called Pre-eclampsia. It can occur after 20 weeks of pregnancy.