Pregnancy calendar

weeks pregnant

13 weeks pregnant - what's happening

Welcome to the second trimester. Fingers crossed, over the next few weeks, you’ll leave the worst of the morning sickness and tiredness behind you.

13 weeks infographic.

What does my baby look like?

Your baby is growing fast - and you may be too! You might hear their heartbeat for the first time.

Your baby now weighs around 25g.

Although you won’t be feeling baby move just yet, they're dancing around inside you. As time goes on their jerky motions are turning into slower, more purposeful ones.

Your baby’s hands find their way to their mouth and sometimes they look like they might be yawning or breathing. At this stage your baby only sleeps for a few minutes at a time but later in pregnancy, they’ll start sleeping for longer stretches and you might even notice a pattern, or routine emerging.

Your baby’s ovaries or testes have developed inside their body and a tiny willy, or clitoris, are now forming where a bump was before.

Your symptoms - what's happening


Not all mums-to-be have a penchant for pickles. If, however, you do - that’s normal too (we won’t judge).

Cravings can be triggered by hormonal changes in your body affecting taste and smell. Also, sharp dips and peaks in your blood sugar levels can leave you hankering after sugary, comfort foods (hence the cake/ice cream/chocolate addiction).

Take a look at our diet and nutrition guides on food swaps for a healthy pregnancy and how to have a balanced diet in pregnancy.

Feeling constipated or bloated?

Hormones can play havoc with your digestive system in pregnancy, leaving you constipated and bloated.

Do you have a headache? Perhaps you’re suffering from cramps, indigestion, dizziness, heartburn or swollen feet?

Here’s our guide to 10 common pregnancy complaints (and how to avoid them).

Actions to take

Healthy eating

If you were struggling with sickness and this has now stopped, you may be feeling hungrier. Although you need to eat food that is good for you and your baby, you don't need to eat for two!

You only need to increase your calorie intake in the third trimester, and then, only by 200 calories a day.

Find out more about managing your weight in pregnancy.

Can I eat packaged salad during pregnancy?

If you buy prepared salad that is pre-washed, it's fine to eat as long as you make sure you keep it in the fridge and don't eat it after the use-by date.

Check the ingredients in any packaged salads you buy to make sure they don't contain foods you should avoid in pregnancy.

Healthy bones for your baby

Calcium is crucial for your baby’s growing bones. Choose low fat yoghurt as a healthy alternative to full fat dairy foods - think about swapping ice cream for a delish dollop of low-fat frozen yoghurt instead.

Here are 10 super snack ideas to help your baby grow.

See ya sofa

You may have felt a bit like hibernating over the last couple of months - but hopefully those days are over. Now’s the time to get active again. Have you thought about signing up to a pregnancy exercise class?

Here’s our guide to staying active in pregnancy.

Work that pelvic floor!

If you haven’t already, this is a good time to start thinking about toning up your pelvic floor muscles.

Pregnancy and giving birth put a big strain on your pelvic floor - the more you can strengthen your muscles now, the better. Working these muscles will also help prevent you leaking wee when you laugh, sneeze or cough. 

You could do a set of pelvic floor exercises every time you brush your teeth, wait for a bus or put the kettle on.

Have you told your boss you’re pregnant yet?

You don’t have to tell your boss that you’re pregnant until the 15th week before the week your baby is due. It may be a good idea to tell them sooner though, especially if you have a strenuous job or need lots of check-ups early in your pregnancy.

“I work for a small company and two other women had announced their pregnancies just before me so I was really worried about how my news would go down, but everyone was so supportive.”

Rachael, mum of one

Read more about working in pregnancy.


1. You and your baby at 13–16 weeks pregnant, NHS Choices: [accessed 7 May 2015] (last reviewed: 10 February 2015; next review due: 10 February 2017)

2. Lennart Nilsson (2009) A Child is Born, Jonathan Cape, p.207.

3. Lennart Nilsson (2009) A Child is Born, Jonathan Cape, p.207.

4. You and your baby at 13–16 weeks pregnant, NHS Choices: [accessed 7 May 2015] (last reviewed: 10 February 2015; next review due: 10 February 2017)

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Last reviewed on April 1st, 2015. Next review date April 1st, 2018.

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  • By Midwife @Tommys on 25 May 2017 - 11:52

    Thank you for your feedback about our nutrition information. We work with experts in the field and the general public to make sure all of our information is accurate and up-to-date so we will definitely consider this point when we next review our nutrition section. If you would like to be involved in the process please email my colleague Amy at [email protected] And if you have any further feedback we’d love to hear from you. Best wishes x

  • By Anonymous (not verified) on 24 May 2017 - 14:10

    The advice about low fat yoghurt being healthier than full fat is totally outdated and not scientifically-backed. You may like to think of updating it!

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