What to expect during the third trimester of pregnancy

Weeks 28 – 32

Your baby is growing fast; they will start out the third trimester weighing about 1 kg and by week 32 they will weigh around 1.7 kg. In this four-week period, your baby will open their eyes and begin noticing light from the outside world.

Weeks 33 – 36

Your baby’s brain and nervous systems are now fully developed, their bones are hardening, and they are laying on fat at a startling rate. By week 36, your baby will weigh about 2.6 kg. If your baby is male, his testicles will be descending from his abdomen into his scrotum.

Weeks 37 – 41

The lanugo (soft, downy hair) that covered your baby in the second trimester will mostly be gone by now, though some babies are born with patches here and there. By this stage of pregnancy, your baby could come any day and should be ready for life outside the womb. Most babies weigh between 3 and 4 kg at birth, and though they are getting pretty squashed inside your uterus, they will be able to move right to the end of your pregnancy, so it’s still important to monitor baby movements until the very end. 

Ideally, by the time your baby is born, they should be in a head-down position with their back against your belly. This is the easiest position for birth. Most babies get into this position by 36 weeks – so it’s not worth worrying before then which position they are in. Babies can move around even during labour!

If your baby is transverse (lying cross-wise across your belly), or breach (bottom down) at full term (37 weeks), you will probably be offered a procedure called external cephalic version (ECV) to try to turn the baby round. This is usually carried out on the labour ward and has about a 50% success rate.

Babies that are still breach on your due date can be delivered vaginally, though you will need to talk to your health professional to determine whether it’s appropriate to try in your specific case. Otherwise, you will be offered a Caesarean section.

Both you and your baby will get bigger over the last three months of your pregnancy. Your body expands and your ligaments relax to accommodate your growing baby and to enable vaginal delivery.

Your breasts are preparing to feed your baby, and you may notice they are leaking colostrum. Once your baby reaches full-term (i.e.37 weeks gestation), you could try collecting some of this amazing milk ready for when they arrive.

Meanwhile, your baby is still developing the functions, skills and fat it needs to survive outside the womb. Breathing practice is ongoing, and the lungs will keep developing right up until the end of pregnancy.

Medical appointments

You’ll be seeing more of your midwife in this trimester than at any other time, so expect your appointments to ramp up. Although there are no more regular ultrasound scans at this point, your midwife will monitor your measurements carefully to make sure the baby is growing as expected and can refer you for additional scans if they need more information.

If you are at risk of gestational diabetes and you haven’t already undergone the glucose screening, it should happen within the first few weeks of your third trimester.

Foetal movements

Your baby will be super active in the third trimester. You might notice that when you’re active, your baby is sleeping, and when you’re resting your baby is active. Monitoring your baby’s movements is the best way to keep an eye on how happy and healthy they are in there.

You don’t need to count movements – there is no ‘normal’ number of kicks – but you should try to get to know their pattern and what’s normal for them. Reduced movements can be a sign that something is wrong, so if you think your baby is moving less than usual, go to your maternity unit for monitoring.

Signs of labour

At some point in this third trimester, you will go into labour.

Signs of labourinclude:

Call your maternity unit if your waters break, you’re bleeding, you’re not yet 37 weeks pregnant, or you’re concerned about your baby’s movements.

Ready to get uncomfortable? Unfortunately, there’s no way around it – accommodating a >3kg baby is a physical challenge. Your body has to grow fairly rapidly to make room, which in itself has side effects. Your stretching skin can become itchy and sensitive, not to mention marked by vivid lines. Your joints and back will ache. You may find yourself short of breath, as your uterus pushes up against your diaphragm, and your squished organs can lead to gastrointestinal problems, such as heartburn, indigestion, trapped wind and constipation. Low blood pressure can make you feel dizzy and weak, while the constant need to go to the loo can drive you mad.

Braxton Hicksare likely to become a more regular feature of your life, as your body prepares for childbirth. Though it shouldn’t be painful, these practice contractions can feel intense.

As you come towards the end of your pregnancy, it’s important you look after yourself. Rest when you need to rest, and don’t pile too much on your ‘to do’ list. Your body needs your energy, right now.

There are some symptoms to be aware of at this stage. Blinding headaches, sudden swelling, blurred vision, vomiting and pain just below the ribs are all symptoms of pre-eclampsia, which can be dangerous to you and your baby. If you suspect you have any of these symptoms, get medical advice immediately – either by calling 111 or speaking to your health professional.

Bleeding is highly unusual at this late stage of pregnancy and should be taken as a warning sign. If you’re experiencing vaginal bleeding or even a significant increase in vaginal discharge, contact your midwife or maternity unit.

As above, reduced movements should be taken seriously. Report to your maternity unit for monitoring. The staff would always rather see you than not, so don’t worry that you’re wasting anyone’s time.

Eating wellremains important in your third trimester. The advice is to up your calorie intake by about 200 calories a day in the final trimester, but more important than the calories you consume is the quality of the food you eat. We’re talking healthy fats (e.g. from avocados, nuts and olive oil), plenty of protein (e.g. from meat, fish and eggs), lots of vegetables (including iron-rich leafy greens) and fruit, plus wholegrain carbohydrates, which will help keep up your fibre intake.

It’s hard to eat well when you’re feeling tired and uncomfortable. Our culture is very much driven towards food-based rewards, which means we use things like sweets, chocolate, chips and crisps to cheer us up when we’re feeling down. Try to think about food as your fuel, instead of your treat. In order to up your energy levels, you need to eat well. Bingeing on comfort foods can be counter-productive in the long run.

Time to pack your hospital bag

It’s never too early to pack your hospital bag (so long as you have somewhere out-of-the-way to store it!). Be prepared for that eventual journey to the labour ward by putting together everything you and the baby will need, including clothes, snacks, nappies and more. We have a whole article dedicated to what to pack in your hospital bag, so take a look and get packing.

Footwear

If you haven’t already given up on the high heels, now’s the time. Your centre of gravity is well and truly shot, so now is not the time to trust your body weight to your swollen toes and a stiletto heel. Get comfy in shoes that allow your feet room to swell, and which support your arches.

Childbirth classes

This trimester is usually when people begin antenatal or childbirth classes. These classes are designed to prepare you for labour, so don’t wait too long to get started. Aim to have finished the course before you reach 37 weeks.

Exercise

Though it can be tempting to spend the last three months on the sofa, it is beneficial to keep moving. Try to maintain some gentle form of exercise; swimming can be nice as it takes the weight off your joints. It’s also important to keep up with the pelvic floor exercises to strengthen those crucial core muscles for birth and beyond.

Sort your maternity leave plans

It can be hard to leave your job in someone else’s hands, but whether you intend to take a few months or a full year off work, you need to make a plan and ensure your employer is fully informed. Get all the paperwork ticked off to make sure you get the benefits you’re entitled to.

What not to do in your third trimester of pregnancy?

The third trimester is a time to take it easy, so try not to take on any new challenges as you and your body have plenty to deal with as it is. Having said that, it’s important to stay active, so don’t give up on exercise altogether if you can help it. A daily walk, regular swim, pregnancy yoga or Pilates can all help keep your strength up.

When should you pack your hospital bag?

It’s never too early to pack your hospital bag. You might find it takes a few weeks to think of everything you want in there!

Your hospital bag needs to include everything you might need during labour, and for you and the baby after the birth. This includes the basics like clothes, nappies and snacks, as well as whatever you’ve decided you would like during labour – for example, massage oil, swim wear for you and your partner, music, etc. We’ve created a handy checklistto help you when you pack.

What causes insomnia in late pregnancy?

Many women find it difficult to sleep during the third trimester. Often, it’s difficult to find a comfortable position to sleep in, and then when you do finally get comfy the baby starts kicking and before you know it you need another wee. Remember, the recommended sleep position in your third trimester is on your side. If you’re normally a back-sleeper, this change alone can be enough to keep you awake. Try to pad yourself around with pillows to get comfortable and make it harder to end up on your back. If you do wake up on your back, don’t panic – just roll back on to your side.

If it’s your busy mind keeping you awake, try listening to calming music or meditation tracks, which can help give you something to focus on that enables you to clear your mind. It’s normal to feel anxious about the huge life change ahead of you, not to mention the birth before that. Talking to your partner, friends and family about your worries can help, as can keeping a journal to ‘download’ your thoughts before you try to go to bed.

What are some signs that labour is approaching?

The physical signs that labour is beginning can include contractions, your water breaking, a ‘show’ (the mucus plug detaching from your cervix), back ache and loose bowels. Some people report feeling a burst of energy – e.g. the sudden need to scrub the floors – as anecdotal evidence that labour is approaching. Obviously, this isn’t scientifically proven, but perhaps you will just ‘know’ that your baby is on their way.

What foods should be avoided in the third trimester?

Continue avoiding the foods that are off limits throughout pregnancy – e.g. unpasteurized dairy products, raw meat, certain types of fish, etc. You should also continue to avoid too much caffeine and eliminate alcohol. There’s nothing specific to avoid during the third trimester, but some people say that certain food types can help kickstart labour. Again, it’s not scientific, but it can be fun to try!

Got questions? At the HiPPBabyClub, we bring you real-world advice and support from HiPP parents, midwives, nutritionists and more. Join our Baby Club to find out more.