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 40 – your third trimester

The wait is nearly over. Within days, you'll get to meet your baby. It's been quite a journey, but the real adventure starts when your little one is born.

What's happening in my body?

If this is your first baby, then you'll have an antenatal appointment this week. Your blood pressure will be checked, your bump will be measured and you'll hand over a urine sample. You know the drill! Your midwife or doctor will be checking for signs of pre-eclampsia, a dangerous condition that's characterised by high blood pressure and protein in the urine.

You're probably getting a lot of practice contractions now, which should not be painful. These are Braxton Hicks contractions. When you start getting labour pains, you'll know all about it! Real contractions hurt when your bump goes tight, and then the pain goes away when the muscles relax.

Labour is divided into 3 stages. The first stage is when you have contractions and your cervix opens up until it's 10cm across (fully dilated). The first stage lasts 6-12 hours, or less if you've had other children. The second stage is where the baby is delivered – and the third stage is when the placenta comes out.

You can read more about what happens during labour here.

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. Have you found this website useful? Do you have any tips for other parents? Send us a picture, as we'd love to see you with your bump or your baby!

From breathing to bananas: 8 tips for your labour

These tips could help you feel in control and manage your pain:

  1. If your contractions start at night, try to sleep your way through as much as possible – the rest will help to prepare you for the birth, and your cervix will dilate while you sleep.

  2. If your contractions start in the day, then keep upright and active as this helps the baby to move down and your cervix to open up. This could speed up your labour and reduce the need for painkilling drugs.

  3. Try different positions. Rock on a birth ball, or put your arms around your partner's neck and lean on them. Just keep moving!

  4. Have a warm bath or shower – it's a tried and tested method of pain relief that's thought to date back thousands of years.

  5. Focus on breathing. You can practise your breathing techniques now. Take deep breaths in through your nose and out through your mouth. Keep your jaw relaxed.

  6. Ask your partner for a massage and involve them in your labour. Having their support and reassurance will encourage your body to produce more endorphins, which are brilliant natural painkillers. Here are some more ways that your partner could support you.

  7. Eat something healthy to keep up your energy levels, like a banana or low-fat yoghurt. Avoid fatty foods, as they could make you feel sick, and steer clear of sugary foods as they'll only give you a quick hit before a slump.

  8. Keep calm and carry on. If you feel relaxed, you will be able to manage your labour and pain much better than if you're stressed.

When your contractions last for at least 60 seconds and come every 5 minutes, call your hospital or midwife.

Will curries and sex bring on labour?

You've probably searched the internet for ways to bring on labour and found tips that range from sex to vindaloos. There's a round-up here which will give you the lowdown on everything from raspberry leaf tea to nipple stimulation.

The upshot is that there are no proven ways to safely bring on labour at home. Get advice from your doctor or midwife before trying anything other than watching and waiting.

Third trimester pregnancy symptoms (at 40 weeks)

Do you feel like you've got PMT? Or do you have lower backache? These could be early signs of labour. Check out these 5 signs that your baby is on the way.

Your signs of pregnancy could also 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 51.2cm long from head to heel, and weighs about 3.5kg. That's approximately the size of 2 Romano peppers and the weight of a small pumpkin.

Your baby is getting rather squashed up now, but should still be moving around in their usual pattern. Movements should not slow down or stop, and if they do, it could be an important sign that something is wrong. If you notice any changes, contact your midwife or maternity unit straight away – there will be someone there to answer calls 24 hours a day.

Action stations

You're probably on leave now. Find out how much leave and pay you're entitled to.

It's a good time to tone up those muscles down under. Gentle 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 between October and March it's best to take a vitamin D supplement every day. Just 10 micrograms is all you need (it's the same for grown-ups and kids). It's worth checking if you're entitled to free vitamins.

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 overdo it, particularly in these last few weeks – listen to your body.

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 2 slices of wholemeal toast and margarine.

Try to eat healthily 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.

You will be offered newborn screening tests for your baby soon after they are born. These screening tests are recommended by the NHS. This is because results from these tests can help make sure that your baby is given appropriate treatment as quickly as possible if needed. It is important to think carefully whether you want to have these screening tests. Your decisions will be respected, and health care professionals will support you. Ask your midwife or doctor for more information about newborn screening.

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