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 18 – your second trimester

What a week! It's all happening now. You could feel your baby move for the first time. Plus you could see your baby in close-up if you choose to have an anomaly scan. Week by week, you're ticking off new milestones in your pregnancy. You may feel happy, sad, excited or nervous – sometimes all at once! It's an emotional roller-coaster, so hold on tight…

What's happening in my body?

You might be starting to feel a bit clumsier as your belly gets bigger. Your breasts may have gone up a size, too, particularly if it's your first pregnancy. Your blood pressure is probably a bit lower than it was, so don't leap up from the sofa, or it could make you feel dizzy.

Your baby has been moving around for the past couple of months, but you wouldn't have noticed because they were so small. Now, you might start to feel some movement – it's like a bubbling or fluttering inside your belly.

You may also notice a line down your stomach, called the linea nigra (Latin for 'black line'). This is normal skin pigmentation and nothing to worry about. It will probably vanish a few months after your baby's born.

Your anomaly scan

You'll be offered an anomaly scan at around 18 to 20 weeks. This is a scan that looks at your baby in detail to see if there is anything unusual about their development and appearance. It can pick up a range of conditions, but not all of them. You don't have to have this scan – it's up to you.

The scan won't hurt you or your baby but it could feel a bit uncomfortable as the sonographer may have to apply a bit of pressure on your stomach to get the best possible view.

Usually, the scan will show that the baby is healthy. However, sometimes the scan could pick up something you're not expecting. If this is the case, then you may be offered further tests. You can decide whether to have them or not.

Is it a boy or a girl?

The sonographer may be able to tell you at this scan – but not everyone wants to know, and it's not always the hospital policy to reveal the sex of the baby. If you don't want to know, then make this clear before you start.

Free prescriptions and dental care

Did you know that prescriptions are free during pregnancy? NHS dental treatment is also free. You'll need a Maternity Exemption Certificate or card (MatEx). Ask your midwife, GP or health visitor for the application form FW8. Your certificate will be valid for up to a year after your baby's due date or date of birth.

Second trimester pregnancy symptoms (at 18 weeks)

With any luck you're getting into the groove and can manage your symptoms as your body expands. You should never feel in agony, or unable to cope, so talk to your midwife or doctor if you find yourself struggling with your day-to-day life.

Your signs of pregnancy could include:

Tommy's, the baby charity, has a further list of common symptoms.

What does my baby look like?

Your baby, or foetus, is around 14.2cm long from head to bottom, and weighs around 190g. That's approximately the size and weight of a sweet red pepper.

Your baby's reflexes are developing this week – and on the agenda will be hearing, feeling, swallowing and sucking. They will also be doing a lot of wriggling around and moving their little arms and legs.

Action stations

This is a good week for planning and getting things done. Make a 'to do' list and start ticking things off – it's amazingly therapeutic. Put 'me time' on the list, in case you forget that you're important too.

This week you could also...

Many women will tell their employer after they've had their first pregnancy scan at around 12 weeks. Once you tell your employer, you have maternity rights and can attend antenatal appointments during paid work time. You can also ask for a risk assessment of your workplace to ensure that you're working in a safe environment.

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 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 third trimester, which starts in week 28. 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.

This week's treat

You're probably busting out of your usual clothes – so get yourself something 'new' that will make you look and feel good. Lots of supermarkets have maternity ranges or try finding something online. You'll be fed up with your maternity wardrobe a few months from now, so there's no need to splash the cash!

Go back to week 17

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