13 weeks pregnant: signs, symptoms and baby development

woman 13 weeks pregnant

by Emily Gilbert |

At 13 weeks pregnant, your placenta is fully developed and you can get ready to announce your pregnancy. Here’s what to expect during week 13 of your pregnancy, what's happening to your baby, what's happening to your body and symptoms you may be experiencing.

How big is my baby at 13 weeks pregnant?

Your baby has grown to about 7cm long or the size of a peach.


What is my body doing at 13 weeks pregnant?

As you reach your second trimester, symptoms such as morning sickness and exhaustion should begin to abate.

By now, your placenta will be fully developed but will continue to grow in size throughout your pregnancy. Your baby is connected to it via the umbilical cord, through which your baby gets enough oxygen and nutrients. Yet the placenta also has an important role in getting rid of waste products such as carbon dioxide and producing many of the important hormones needed for your baby’s development. It might not be very pretty to look at (don’t Google image it if you’re still feeling delicate) but it does a truly amazing job for your baby.

This week, you might see the first signs of that baby bump – it usually shows up between 12 and 16 weeks, but this completely depends on your body and your baby. A showing bump can be one of the biggest pregnancy excitements and you can now get ready to announce you’re expecting.

What’s my baby doing at 13 weeks pregnant?

At the moment, your baby’s head still makes up about half the size of her body and her eyelids are fused shut to protect her eyes for the next few months.

During week 13, your little one will start developing bones in her arms and legs and her intestines, which up until now have been growing inside the umbilical cord, will move to their permanent address in your baby’s abdomen. This week the placenta is also growing, and getting ready to feed and nourish your foetus for the next few months. Your baby will also now start developing his or her reproductive organs, but it’s probably too soon to see this on an ultrasound just yet.

Another cute development this week – your little one’s vocal cords, something we’re sure she’ll use frequently once she’s born!

6 common symptoms to look out for at 13 weeks pregnant:

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Increased energy
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1) More energy

At last! Now the placenta is taking over, you should feel like you’ve got a bit more of a spring in your step. Consider using this energy and adding some exercise to your routine, but don’t go mad!

What you should be doing this week

If you find you’ve been showing for weeks and you’re already bursting out all of your clothes, it might be worth double-checking for twins. If your first ultrasound has confirmed there’s only one little bun in the oven, do not worry, this could mean your due date isn’t quite right and you’re further along than you thought (or that you’re full of gas and are just bloated).

Below is a checklist of things you may wish to start doing at 13 weeks pregnant:

Tell work about your pregnancy - if you haven't already, now may be a good time to tell your work about your pregnancy. A lot of women usually leave his until their first scan at 12 weeks. Make sure you know your maternity rights once you've told them.

Pelvic floor exercises - now is a good time to start toning and tightening your pelvic floor, which help prevent you leaking when you laugh, sneeze or cough.

Give up smoking and alcohol - as experts aren't entirely sure how much alcohol you can drink safely during pregnancy, it's best to avoid it altogether and not risk it. Smoking however, will harm your unborn baby. If you're struggling to do either, reach out to your GP or midwife for support.

Eat a healthy diet- it's important to make sure you're eating a well balanced and nutritious diet to make sure you and your baby are getting those all important nutrients.

Take me back to week 12

Take me to week 14

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