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!

3rd 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.

Week 40 – your 3rd 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. 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 1st stage lasts 6 to 12 hours, or less if you've had other children. The 2nd stage is where the baby is delivered – and the 3rd stage is when the placenta comes out.

Read about what happens during labour on the NHS website.

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

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 birth 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.

  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 birth 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. Do something that helps you to relax. If you feel calm, you will be able to manage your labour and pain much better than if you're stressed.

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 Tommy's has information on what might help bring on labour from raspberry leaf tea to nipple stimulation.

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.

3rd 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:

You may also experience symptoms from earlier weeks, such as:

Read Tommy's guide to common pregnancy 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 maternity leave and pay you're entitled to.

It's a good time to tone up your pelvic floor muscles. Gentle pelvic floor exercises can help to prevent leakage when you laugh, sneeze or cough. Get the muscles going by pretending that you're having a wee and then stopping midflow.

Do your best to stop smoking, give up alcohol and go easy on the tea, coffee and anything else with caffeine. Ask your midwife or GP for support if you need it.

To keep bones and muscles healthy, we need vitamin D. From late March/early April to the end of September, most people make enough vitamin D from sunlight on their skin. However, between October and early March, you should consider taking a daily vitamin D supplement because we cannot make enough from sunlight.

Some people should take a vitamin D supplement all year round, find out if this applies to you on the NHS website. You just need 10 micrograms (it's the same for grown-ups and kids). Check if you're entitled to free vitamins.

It's recommended that you do 150 minutes of exercise a week while pregnant. 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.

There's no need to eat for 2. Now you're in the 3rd 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 keep it to yourself. It's important that you ask for help if you need it.

Having another baby 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. 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.

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 these tests can make sure that your baby is given appropriate treatment as quickly as possible.

It is important to think carefully whether you want to have these screening tests. Your decisions about whether or not you want this tests will be respected, and health care professionals will support you.

Ask your midwife or doctor for more information about newborn screening.

Go back to week 39

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