13 weeks pregnant: signs, symptoms and baby development

woman 13 weeks pregnant

by Emily Gilbert |
Updated on

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:


6 common symptoms to look out for at 13 weeks pregnant

Increased energy1 of 6

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!

Increased sex drive2 of 6

2) Increased sex-drive

As your second-trimester approaches, you might find a boost in your sex drive! However, it’s worth noting if you’ve got a history of the early labour of miscarriage, it’s worth checking with your doctor beforehand.

Vaginal discharge3 of 6

3) Vaginal discharge

Otherwise known as leukorrhea, this thin, milky, mild-smelling or odourless discharge is another perfectly normal symptom, caused by the production of oestrogen during pregnancy. Its job is to protect the birth canal from infection and keep it healthy during pregnancy, so don’t worry about using special wet wipes to clean it away. The downside is it can cause a mess of your favourite underwear, so wear a thin panty liner around this time.

Visible veins4 of 6

4) Visible veins

You might not like them, but these are super important during pregnancy and are a sign of the increased blood supply to your growing baby.

Heartburn5 of 6

5) Heartburn

Heartburn is very common and probably won’t ease up any time soon. During pregnancy the muscle at the top of the stomach relaxes which allows digestive acid to rise and cause that familiar burning in the chest. Stay away from spicy or fatty foods and keep those antacids handy!

Constipation6 of 6

6) Constipation

We’ve mentioned this before, but during pregnancy, those all-important hormones create some unwanted side effects, and this is one of them! Your bowel muscles relax, meaning they are less effective at moving things along, which can leave you feeling pretty uncomfortable. Our top tips? Add some high-fibre snacks to your diet – fruit, vegetables and whole grains are good options.

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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