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Week 20

You're now halfway through your pregnancy!

What's happening in my body?

You may have your anomaly scan this week. The sonographer will be checking your baby's development and will also examine your placenta (that's the pancake-shaped organ that feeds your baby and removes waste).

You might find yourself being woken up at night by sudden sharp pains in your calves.

It's probably cramp, which is common in pregnancy and caused by muscular spasms. Rub the muscle hard or pull your toes up towards your ankle.

Exercising more in the day could help you avoid this, and you could try these foot exercises.

Maternity Certificate to claim maternity pay and benefits

Ask your doctor or midwife for a Maternity Certificate, also known as a MAT B1 form. It's issued from 20 weeks onwards.

You'll need it to claim maternity pay and benefits.

Whooping cough jab

Whooping cough is on the rise – but you can protect your baby from this dangerous condition by having a vaccination.

The NHS recommends that all pregnant women should have the jab, ideally between 16 and 32 weeks.

The immunity that you get will be passed on to your baby through the placenta and then offer protection until the routine jab that most babies have at 2 months.

2nd trimester pregnancy symptoms (at 20 weeks)

Your signs of pregnancy this week could 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 25.6cm long. That's approximately the size of a banana.

Measurements are now taken from head to heel. In earlier weeks, babies are measured from the head to the bottom because the legs are curled up and hard to see.

They are now covered in a white, greasy layer of "vernix". It's thought this protects their delicate skin from drying out in the amniotic fluid. This slippery layer also helps babies to make their way down the birth canal.

Your baby will be getting more active each day. As well as kicking, punching and turning around, your baby could be sucking their thumb – this develops their sucking reflex, which they'll need to feed once they're born.

You may start to feel a bubbling or fluttering in your belly – this could be your baby moving around.

Composite. One side shows a foetus attached to the placenta by the umbilical cord. The foetus is recognisable as a baby. Other side shows a person holding a banana in one hand.
Your baby is about the size of a banana

Action stations

Think about telling your work

You do not have to tell your employer for several more weeks, but as soon as you do, you will have maternity rights and can attend antenatal appointments during paid work time. You can also ask for a risk assessment of your work place to ensure that you're working in a safe environment.

If you want to wait, the latest you can leave it is 15 weeks before the baby is due, which is around week 25.

Start doing pelvic floor exercises

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 pee and then stopping midflow.

Visit Tommy's for more information on pelvic floor exercises.

Antenatal classes

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.

Even if you've had children before, antenatal classes are 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.

Smoking, drinking and caffeine in pregnancy

Do your best to stop smoking and give up alcohol, and go easy on the tea, coffee and anything else with caffeine.

Ask your midwife or GP for support.

Vitamins in pregnancy

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.

Exercising in pregnancy

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.

Healthy eating

There's no need to eat for 2. You do not need any extra calories until the third trimester, which starts in week 28.

You just need to eat a healthy balanced diet, with a variety of different foods every day, including plenty of fruit and veg. Have a look at our guide to healthy eating in pregnancy.

You may be able to get free milk, fruit and veg through the Healthy Start scheme.

More in week-by-week

Week 21

As you start the 2nd half of your pregnancy, you'll be entering a period of rapid growth. Your baby is getting ready for life outside the womb and developing essential skills including sucking and breathing.

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