Week-by-week guide to pregnancy

pregnant woman sitting down
When you're pregnant, you have lots of questions. Our week-by-week pregnancy guide is packed with lots of useful information. From what's happening inside your body, to how your baby is developing, and tips and advice on having a healthy pregnancy – this is your one-stop pregnancy guide!

Third trimester

Our week-by-week pregnancy guide is full of essential information. From advice on writing a birth plan to what to expect at antenatal classes, you'll find it all here. Happy reading!

Week 37 – your third trimester

Now here's something amazing! Your baby could come any day now – and it wouldn't be 'early'. That's right, your baby is now 'full term', which means that they're probably big enough, and mature enough, to survive in the outside world. However you still may have to wait another few weeks, as babies tend to come in their own sweet time.

If you're carrying twins, then you will probably give birth this week. Twin pregnancies rarely go beyond 38 weeks. The Twins and Multiple Birth Association (TAMBA) could be a handy source of information for you.

Good luck everyone!

What's happening in my body?

Around 95 per cent of babies will now be head down, facing their mother's back, which is the best position for labour. When the baby's head moves down into the pelvis, it's said to be 'engaged'. You might see your bump drop a bit when this happens. Random people at the bus stop might start telling you that the baby's due any minute – but actually it could still be several weeks.

If your baby's still in the bottom-down position (breech) don't worry, there's still time for them to turn. Some babies don't move into place until labour starts. When you're sitting down, try leaning forwards, with your hips above your knees. It's not a proven technique but many women say that it coaxes the baby into position and it certainly can't do any harm.

You might find that you're getting more vaginal discharge now and Braxton Hicks contractions – these are the 'practice' contractions around your bump, which can feel uncomfy but shouldn't be painful. You could also be getting a sudden urge to spring clean. That's your 'nesting' instinct kicking in, and partners can get it too! It's not a scientifically proven phenomenon but many people report feeling the urge to tidy and clean shortly before the baby comes. Just don't overdo it, you should try to rest as much as possible.

Talk to your midwife about group B strep

Group B strep is a common bacteria – up to 2 in 5 people have it living in their body. If you carry group B strep while you're pregnant, there's a small risk it could make your baby seriously ill. Most group B strep infections in newborn babies are preventable.

For more information talk to your midwife, or visit the Group B Strep Support website.

Tell us about your pregnancy!

We hope you're having a happy pregnancy. Please contact us through Start4Life's Facebook page and let us know how you're getting on. Have you found this website useful? Do you have any tips for other mums? Send us a picture, as we'd love to see you with your bump or your baby!

5 signs that baby's on the way

Look out for these telltale signs – and be patient! Remember, babies come when they're good and ready…

1. The 'show': you may see a sticky blob of mucus in your pants, which might be yellow or bloody. This plug used to seal up your cervix and the fact that it's come undone shows that something's happening down there. It's called a 'show' and can be one of the first signs of labour. However, you could still have days, or even weeks to wait…

2. Your waters break (rupturing of the membranes): don't expect a massive gush like you see in films – it could just be a little 'pop' and a trickle. The liquid should be clear. If it drips, then use a pad, not a tampon. Contact your midwife or doctor immediately if it's smelly or coloured.

3. Backache: this is caused by your baby's head bashing away at your spine. When their head meets your sacrum (tailbone) it's agony!

4. The urge to go to the toilet: this is caused by your baby's head pressing on your bladder or bowels. You may find that you wet or poo yourself. It's very common, so don't be embarrassed!

5. Contractions or tightening around your bump: it hurts when your bump goes hard, and then the pain goes away when the muscles relax. It feels like period pains to start with or a heavy dragging feeling in your pelvis and legs. Then your contractions get longer, stronger and more frequent.

It's time to call your midwife or hospital when your contractions last for at least 60 seconds and come every 5 minutes. Phone straight away if you're losing blood, in too much pain, worried that something's wrong, or if your baby stops moving.

Third trimester pregnancy symptoms (at 37 weeks)

As your baby moves down into your pelvis, you may start to feel some relief from pregnancy symptoms such as heartburn, indigestion and nipping to the loo every 5 minutes. Alternatively, you may still be suffering, in which case, hang on in there, it really, truly, won't be long now.

Your signs of pregnancy could include:

Tommy's the baby charity has produced a pregnancy guide with a further list of symptoms.

What does my baby look like?

Your baby, or foetus, is around 48.6cm long from head to heel, and weighs about 2.9kg. That's approximately the length of 2 cucumbers and the weight of 14 baked potatoes.

Your baby will be trying out different facial expressions, such as frowning and smiling. They might also practise silent crying. This is just random – it's not linked to sadness or happiness.

By now, you will hopefully know when your baby's active and when they're calmer. These patterns are likely to continue after the birth.

Action stations

Read a little bit about postnatal depression and encourage your partner to do the same – either one of you could develop symptoms after the birth, although it's most likely to affect you. More than 1 in 10 women will develop this condition, usually in the first year. Signs include low mood, lack of energy, sleeping problems and frightening thoughts. It's important to get help from your doctor or health visitor if either of you develop these symptoms.

This week you could also...

You may be on your maternity leave or about to stop work..

It's a good time to tone up those muscles 'down under'. Gentle pelvic floor exercises can help to prevent leakage when you laugh, sneeze, cough or jump around on your future baby's trampoline. Get the muscles going by pretending that you're having a wee and then stop the 'urine' in midflow.

Do your best to stop smoking, give up alcohol and go easy on the cappuccinos. We know that's easy to say, but hard to do. Ask your midwife or GP for support.

We can usually get enough vitamin D from sunlight, but as we are at home a lot more at the moment, you may not be getting enough. If you're pregnant, or breastfeeding, you should consider taking a daily vitamin D supplement. It's worth checking if you're entitled to free vitamins.

Get moving! It's recommended that pregnant women do 150 minutes of exercise throughout the week. You could start off with just 10 minutes of daily exercise - perhaps take a brisk walk outside. Check out Sport England's #StayInWorkOut online exercises (scroll to the pregnancy section). Listen to your body and do what feels right for you.

Don't eat for two! Eat for you. Now you're in the third trimester, you may need an extra 200 calories a day, but that's not much. It's about the same as two slices of wholemeal toast and margarine.

Try to eat healthily, with plenty of fresh fruit and veg, and avoid processed, fatty and salty foods. You may be able to get free milk, fruit and veg through the Healthy Start scheme.

How are you today? If you're feeling anxious or low, then talk to your midwife or doctor who can point you in the right direction to get all the support that you need. You could also discuss your worries with your partner, friends and family. You may be worried about your relationship, or money, or having somewhere permanent to live. Don't bottle it up – you're important, so ask for help if you need it!

Getting pregnant again is probably the last thing on your mind! However, now is a good time to start planning what type of contraception you would like to use after your baby is born. Making this decision when you're pregnant will give you one less thing to think about when you're looking after a newborn baby. Getting pregnant again could happen sooner than you realise and too short a gap between babies is known to cause problems. Talk to your GP or midwife to help you decide and get everything in place.

This week's treat

Feeling tired and frazzled? Then turn your sofa into a luxury spa. Lie back, shut your eyes, and put cold black teabags on your eyelids to reduce puffiness. Relax for 5 minutes, then carefully rinse and dry your eye area.

Now make your own face mask, to get back your glow, with one mashed-up ripe avocado, a tablespoon of yoghurt, and a dash of lemon juice. Leave on your skin for 20 minutes while you read a magazine. Bliss!

Go back to week 36

Go to week 38

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