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 28 – your 3rd trimester

Welcome to the 3rd trimester! Pregnancy is divided into 3 stages, known as trimesters…. and you're now in the 3rd stage. Over the next few weeks, you will probably start to feel a bit more uncomfortable and tired.

What's happening in my body?

You may be getting a bit of heartburn and indigestion. That's down to your growing baby and hormones affecting your digestive system.

Your back will also be under strain, due to the extra weight you're carrying around. Your joints and ligaments will also be looser than usual.

Your ankles, feet and face could be puffing out a bit, particularly when it's hot. This is probably due to water retention, but get it checked out, just in case it's pre-eclampsia. This is a condition where you may feel perfectly well, but then your blood pressure can get dangerously high, very quickly.

Rest can help with a lot of your symptoms, so make sure you get lots of it. But if you are worried about anything at all, talk to your midwife or doctor, or call NHS 111.

3 ways to bust germs

Make sure you know about some of the harmful infections in pregnancy, so that you can do your best to avoid them.

Here are 3 ways you can protect your unborn baby…

  1. Wash your hands regularly with soap and water for at least 20 seconds, particularly if you're in contact with children or nappies, as they could carry a virus called CMV (cytomegalovirus).

  2. If you have a cat - wear gloves when emptying the cat litter tray, or ask someone else to deal with it. That's because cat poo can contain a bug that causes the dangerous toxoplasmosis infection. You should also wear gloves when gardening, in case you come into contact with animal poo.

  3. If you have not had chickenpox let your doctor or midwife know if you come into contact with anyone who could be infectious. The disease can be spread up to 2 days before spots appear, until 5 days afterwards. It's safest for you when there are no new blisters or moist crusts on the spots.

If you're worried about coronavirus, have a look at the guidance from Royal College of Obstetricians and Gynaecologists on coronavirus and pregnancy.


Nosebleeds are common in pregnancy, due to hormonal changes, and can even strike when you're asleep. Here's what you can do:

  • sit or stand up - don't lie down
  • pinch your nose just above your nostrils for 10 to 15 minutes
  • lean forward and breathe through your mouth
  • put an icepack (or a bag of frozen peas wrapped in a tea towel) at the top of your nose

Read more tips for stopping nosebleeds.

3rd trimester pregnancy symptoms (at 28 weeks)

You may start getting new symptoms now, such as nosebleeds and indigestion.

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 37.6cm long from head to heel, and weighs about 1kg. That's approximately the size of a pineapple, and the weight of a big bag of brown sugar.

Your baby's heart rate is changing all the time. Around week 5 or 6, when it was first detectable, it was around 110 beats per minute (bpm). Then it soared to around 170 bpm in week 9 and 10. Now, it's slowed down to around 140 bpm and it will be around 130 bpm at birth.

That's still a lot faster than your heart rate, which will be around 80 to 85 beats per minute. This is partly because babies' hearts are so small that they can't pump much blood, but they can make up for this by going faster. It also helps to keep them warm.

Your baby's heart can be heard through a stethoscope. Someone else might be able to hear it by putting an ear to your pregnant belly – give it a go, but it's tricky finding the right spot.

Action stations

It's time to work out where your baby will sleep, and it's best to do this sooner, rather than later, before you start running out of energy. Your baby will spend a lot of time in a cot, so make sure it's safe. If you're buying a new cot, look for the British Standard mark BS EN 716-1. Read more about what you need for your baby.

This week you could also...

You have maternity rights. You can ask for a risk assessment of your work place to ensure that you're working in a safe environment. You should not be lifting heavy things and you may need extra breaks and somewhere to sit. You can also attend antenatal appointments during paid work time.

It's a good time to tone up your pelvic floor muscles. Gentle 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. Visit Tommy’s for more ideas about pelvic floor exercises.

Ask your midwife or doctor about online antenatal classes – they start around now. The charity Tommy's has lots of useful information on antenatal classes and preparing you for birth.

Even if you've had children before, they're still worth going to as you can meet other parents-to-be. The NCT offers online antenatal classes with small groups of people that live locally to you.

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.

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 and 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.

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. 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. 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.

You and your family should follow the government and NHS guidance on coronavirus (COVID-19):

  • read government guidance on how to stay safe from COVID-19
  • get NHS advice about COVID-19
  • use the NHS COVID-19 app for England and Wales – it's the fastest way of knowing when you've been exposed to COVID-19
  • To find out about about COVID-19 and pregnancy, childbirth and breastfeeding, have a look at advice on the:

  • NHS website
  • Breastfeeding Network
  • World Health Organization
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