Week-by-week guide to pregnancy

group of pregnant women
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!

Second trimester

Our week-by-week pregnancy guide is full of essential information. From staying fit in pregnancy to advice on your maternity rights, you'll find it all here. Happy reading!

Week 27 – your second trimester

Pregnancy is divided into three chunks, called trimesters. Next week, you will start the third and final trimester.

What's happening in my body?

You're probably putting on a few pounds now and you may be feeling bloated and constipated. This is partly because your stomach is being squeezed by your growing baby, and partly due to the pregnancy hormone, progesterone. It might help to drink lots of water, choose high fibre options (such as brown bread, rather than white) and eat lots of fresh fruit and veg.

Read more tips to deal with bloating.

Bit on the side: the best sleeping positions

Should you sleep on your back or side? The NHS guidance says that sleeping on either side is better than sleeping on your back.

That's because after week 28, research suggests that sleeping on your back can double the risk of stillbirth. It's also more likely to give you backache, constipation and piles.

Here are some tips for a safe and sound night's sleep:

  • support your baby bump with a pillow
  • keep your knees and legs bent
  • put another pillow between your legs
  • if you roll onto your back, don't worry, just roll back onto your side again

Are you fit to fly?

This is probably the last week you can fly anywhere without a 'fitness to fly note' from your midwife or GP. If you have a note, which confirms that your pregnancy is uncomplicated, then you can usually travel by plane up until the end of week 36 if you're having a single baby, or the end of week 32 if you're having a multiple birth. Double check the cut-offs with your airline. Find out more about travel during pregnancy.

Second trimester pregnancy symptoms (at 27 weeks)

You may be feeling tired now, so nap when you can. Your partner might mention that you're snoring more. Snoring is very common in pregnancy as your nasal passages are more likely to become swollen and blocked.

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 36.6cm long from head to heel, and weighs about 875g. That's approximately the size of a big leek, and the weight of a head of cauliflower.

Your baby's lungs are now capable of breathing – and that's a big deal. Your baby is also getting plumper by the day. A few weeks ago, your baby looked a bit like a wrinkled prune. Now the folds of skin are being filled out by fat, and all their organs are maturing, as your baby prepares for life outside the womb.

Action stations

Do you know where you would like to give birth? This is a great time to start thinking about it. If you're concerned about how coronavirus might affect your birth plan, visit the Royal College of Obstetricians and Gynaecologists for the most up-to-date advice.

This week you could also...

You have maternity rights and if you're worried about your safety at work, then talk to your employer. You shouldn't be lugging anything around, 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 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. Visit Tommy’s.org for more ideas about pelvic floor exercises.

Ask your midwife or doctor about online antenatal classes – they may be able to recommend one. The charity Tommy's has lots of useful information on antenatal classes and preparing you for birth.

Ask your partner if they would like to take part in the antenatal classes. 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 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.

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. You don't need any extra calories until the 3rd trimester, which starts in week 28. 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 doctor or midwife 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.

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