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 13 – your second trimester

Amazingly you are now a third of the way through your pregnancy! You're hopefully through the worst of your symptoms and the risk of having a miscarriage has plummeted. This is the glorious second trimester… enjoy it!

What's happening in my body?

Well? Can you see it yet? A small baby bump may now be visible as your womb grows upwards and outwards. If you've been feeling the urge to pee a lot, then that should stop as the womb shifts away from your bladder. By the way, it shouldn't hurt when you pee. If it does, then see your doctor, as you could have a urine infection.

Meanwhile, there's a lot more blood pumping around your pelvic area and some women find that it sends their sex drive through the roof. It could also make you feel more thirsty. So drink more water or have more sex – that's up to you! Sex during pregnancy is perfectly safe, unless your midwife or doctor has advised you otherwise.

Infection alert

It's impossible to avoid contact with all infections while you are pregnant – but there are ways you can protect yourself and the baby from many harmful viruses and bacteria:

  1. Try to avoid contact with anyone who has chickenpox or rubella – talk to your doctor or midwife ASAP if you think you could be infected.
  2. Delegate emptying the cat litter tray, as the faeces could contain a bug called toxoplasma gondii. This can cause an infection called toxoplasmosis that could damage your unborn baby.
  3. You can also get toxoplasmosis from certain foods. Foods to avoid during pregnancy include undercooked meats, cured meats like salami, and unpasteurised goats' milk and cheese.
  4. Seek advice before travelling to any area affected by the Zika virus, as the virus can cause birth defects.

Read more about infections in pregnancy.


All pregnant women should follow the government advice on coronavirus:

Teething troubles

Have you got swollen, painful and bleeding gums? That's common during pregnancy. Your teeth are more likely to get covered in sticky plaque, and if it's not removed then that can lead to gum disease. This is due to your pregnancy hormones – you can pretty much blame your hormones for everything over the next six months!

The good news is that you can get free dental care on the NHS during pregnancy and for a year after your baby is born. You'll need to ask your doctor or midwife for a maternity exemption certificate.

Brushing up

You already know the basics – clean your teeth twice a day, avoid sugary snacks and drinks, and don't smoke or it will make any gum disease even worse. But did you also know that…

  • a soft toothbrush is best for sensitive gums
  • scrubbing away could make your gums flare up, so brush in gentle circles, up and down
  • if you're sick, then you can protect your teeth by rinsing your mouth out with water, as this flushes away the harmful acid in your vomit
  • it's best to avoid mouthwashes containing alcohol while you're pregnant, but there are alcohol-free options that will help to reduce plaque there are more tips here

Second trimester pregnancy symptoms (at 13 weeks)

Thankfully we've waved goodbye to the tricky first trimester. With any luck, you can now enjoy your pregnancy, without being sick or rushing off to the loo every five minutes! Of course, there will be niggles but you shouldn't be in pain, and if you are, see your doctor or midwife as soon as possible.

Your signs of pregnancy could include:

  • swollen and bleeding gums (see box 'Brushing up')
  • pains on the side of your belly caused by your expanding womb (known as 'round ligament pains')
  • headaches
  • nosebleeds
  • bloating and constipation
  • indigestion and heartburn
  • sore breasts
  • leg cramps
  • feeling hot
  • dizziness
  • swollen hands and feet
  • urine infections
  • vaginal infections
  • darkened skin on your face or brown patches – this is known as chloasma or the 'mask of pregnancy'
  • greasier, spotty skin
  • thicker and shinier hair
  • symptoms from earlier weeks, such as morning sickness, weird pregnancy cravings, a heightened sense of smell, mood swings, a white milky pregnancy discharge from your vagina and light spotting (seek medical advice for any bleeding)

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

What does my baby look like?

Your baby, or foetus, is around 7.4cm long from head to bottom, which is about the size of a nice ripe peach. The weight is about 25g, which is as heavy as a toothbrush with toothpaste on it.

Your baby's ovaries or testes are fully developed inside and final tweaks are being made on the outside. The baby is moving around, doing a strange dance. At first the movements are very jerky and random but then they start to look more deliberate. You won't feel the kicks and punches until around week 17. Some babies suck their thumb in the womb. It's so cute but it actually serves a purpose as it helps to develop their sucking reflex. They'll need this when it comes to feeding time in the big wide world.

Action stations

Put any extra energy to good use. This week you could…

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 as we are at home a lot more at the moment, you may not be getting enough. If you're pregnant, or breastfeeding, you should consider taking a daily vitamin D supplement. 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

Finding time to exercise isn't easy – but this week, put your fitness first. Try something new, like yoga for pregnancy. Turn your phone off and have a go at these gentle exercises. As well as helping to clear your head, being fit can improve your muscle tone and stamina, and that could come in very handy during labour.

Go back to week 12

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