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 15 – your second trimester

If you regularly travel on public transport, then you might want to order a badge to prompt other commuters into giving up their seat for you. You might feel fine now, but as you get bigger, you will be more unstable on your feet, and falling over could be stressful and even dangerous.

Pregnancy can be exhausting both physically and emotionally. The pregnancy journey can sometimes feel like an emotional roller coaster, for you, and your partner. Remember to keep talking to each other – being open about your feelings can help you both feel more supported.

What's happening in my body?

Things are tightening up in your tummy. Your baby is growing quickly and comes with a lot of packaging (the amniotic sac and fluid) and their own food supply (placenta). You could start getting the odd jabbing pain on the sides of your bump. It's known as 'round ligament pain', and putting your feet up and resting can help.

Your skin could also feel a bit itchy. Try rubbing an unperfumed moisturiser over your stomach, wear loose cotton clothing and have a cool bath. If the itching starts to drive you crazy, and particularly if it strikes at night, then see your doctor or midwife, as it could be the sign of a liver condition called 'obstetric cholestasis'. However, it's much more likely to be caused by your hormones.

That's pants!

Have you noticed a lot of discharge in your knickers? Many women get this. There's more blood flowing around your pelvic area and that can cause your body to produce more of the milky fluid called leucorrhoea that keeps your vagina clean and free from infection. See your doctor or midwife if:

  • it changes colour – it should be clear, white or creamy.
  • it starts smelling badly – it should smell slightly musky, not strongly of fish or anything else.
  • it changes texture – for example, it starts going frothy or looks like cottage cheese.
  • you get pain when peeing.
  • you feel itchy or sore.

Any of these signs could mean that you've got a vaginal infection, so get checked out as this could be easily treated.


If you have a vaginal infection, it's most likely to be thrush, which is a common yeast infection. Signs include a lumpy white discharge, itching around your vagina, and stinging when you pee or have sex. To help prevent thrush:

  • wear loose cotton underwear
  • wash with unperfumed soap, and try to avoid scented body washes
  • avoid scented bath products
  • steer clear of sex until it's cleared up There are more tips to beat thrush here.

Second trimester pregnancy symptoms (at 15 weeks)

Your pregnancy symptoms may include:

  • swollen and bleeding gums
  • 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 10.1cm long from head to bottom, which is about the size of an apple. The weight is around 70g, which is the same as a small bag of salad.

This week, your baby has been busy growing a soft layer of hair, called 'lanugo', all over the body.The eyebrows and eyelashes are also starting to sprout.

Your baby's eyes are now sensitive to light. Although they're firmly shut, they could pick up a bright light in the world outside your womb.

Around now, your baby will start hearing too. Talk to your baby and they will probably hear you. They will also hear your heartbeat and any noises made by your digestive system.

Action stations

This is a good week to go, go, go and sort out a few of these jobs. Find time in your schedule for resting too, as you don't want to overdo it.

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

Call a friend – connecting and being sociable with other people is important for your mental wellbeing. If you don't know many people, try chatting to someone at an online antenatal class. Chat about your symptoms, swap mocktail recipes… or just have a laugh and get your happy hormones working overtime!

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