Need to talk? Call 1800 882 436.
It's a free call with a maternal child health nurse. *call charges may apply from your mobile

Is it an emergency? Dial 000
If you need urgent medical help, call triple zero immediately.

beginning of content

Pregnancy at week 13

4-minute read

Your baby

Your baby is now fully formed and looks much more like a human being. They are about 7.5 cm long — about the size of a peach — and weigh about 30g. They are moving about vigorously in your uterus and they can move their arms and legs, suck their thumb and form a fist.

Their organs, including the liver and pancreas, are starting to function. The vocal cords are beginning to develop, and they have soft hair on their eyebrows and head. They are growing a penis or clitoris, but these are too small to be seen during an ultrasound.

The kidneys produce urine, which becomes amniotic fluid. The baby practises breathing and swallowing the fluid.

Your baby at 13 weeks

Length:7.5cm
Weight:30g

Your body

At 13 weeks, you have officially entered the second trimester of pregnancy. If morning sickness is still a problem, talk to your doctor or midwife about how to manage it.

Your bump might start to show and you might feel the ligaments stretching in your tummy and groin.

You may notice more visible veins, especially in your breasts. You may also be tired, have food cravings or food aversions, or have heartburn, indigestion or constipation.

Things to remember

The chances of having a miscarriage decrease once you enter the second trimester. Many people therefore decide to share the news of their pregnancy at this time. Chat with your partner about how you want to do this, and be prepared in case people don’t react in the way you hope for.

You don’t have to tell your employer that you’re pregnant. If you want to take maternity leave, however, you will need to give your employer 10 weeks’ notice. It’s worth thinking early about how you will manage life with a baby. If you haven’t already, now is a good time to find out more about your parental rights and entitlements.

If you haven’t already had prenatal screening or diagnostic tests, now is also the time to organise appointments them if you want to. At 13 weeks you can have a nuchal translucency scan (an ultrasound) or chorionic villus sampling (CVS) if there are any concerns that your baby may have Down syndrome or some other genetic disorders.

Read next


Pregnancy at week 14

Your pregnancy at 14 weeks

Learn about your pregnancy journey and what is happening to you and your baby.

Speak to a maternal child health nurse

Call Pregnancy, Birth and Baby to speak to a maternal child health nurse on 1800 882 436 or video call. Available 7am to midnight (AET), 7 days a week.

Learn more here about the development and quality assurance of healthdirect content.

Last reviewed: April 2022


Back To Top

Need more information?

Unplanned Pregnancy

Read this article to learn more about unplanned pregnancy and what your options are. Unplanned pregnancy means becoming pregnant when you weren’t planning it.

Read more on Rahma Health website

Pregnant with twins? About twin pregnancy | Raising Children Network

Pregnant with twins? Twin pregnancy can have more complications, so you’ll need more check-ups. Here’s what to expect in your pregnancy and antenatal care.

Read more on raisingchildren.net.au website

Screening tests in the first 3 months of pregnancy

You may wish to find out early in your pregnancy if your baby is at increased risk of a serious health condition by having a screening test in your first trimester (the first 3 months of pregnancy).

Read more on WA Health website

Travel and pregnancy

With the proper precautions, and armed with information on when to travel, vaccinations and insurance, most women can travel safely well into their pregnancy.

Read more on Pregnancy, Birth & Baby website

Glossary of pregnancy and labour

Glossary of common terms and abbreviations used in pregnancy and labour.

Read more on Pregnancy, Birth & Baby website

Second trimester: pregnancy week by week | Raising Children Network

Pregnant? In our pregnancy week by week guide, you can find out what to expect and follow your baby's development during the second trimester.

Read more on raisingchildren.net.au website

Pregnancy at week 12

By week 12, your baby is the size of a plum but fully formed, with their organs, muscles, limbs and bones in place.

Read more on Pregnancy, Birth & Baby website

Bonding with your baby during pregnancy

Bonding with your baby doesn’t have to wait until they are born. Pregnancy can be the perfect time to start forming an attachment with them. Find out how here.

Read more on Pregnancy, Birth & Baby website

Ultrasound scans during pregnancy

Ultrasound scans will help you and your doctors monitor your baby’s health throughout your pregnancy. Find out more, including about why you might need one.

Read more on Pregnancy, Birth & Baby website

Toxic household products to avoid during pregnancy

Find out about the toxic products you should try to avoid during pregnancy. Are they dangerous? And what should you do if you’re exposed?

Read more on Pregnancy, Birth & Baby website

Call us and speak to a Maternal Child Health Nurse for personal advice and guidance.

Need further advice or guidance from our maternal child health nurses?

Healthdirect Australia acknowledges the Traditional Owners of Country throughout Australia and their continuing connection to land, sea and community. We pay our respects to the Traditional Owners and to Elders both past and present.

This information is for your general information and use only and is not intended to be used as medical advice and should not be used to diagnose, treat, cure or prevent any medical condition, nor should it be used for therapeutic purposes.

The information is not a substitute for independent professional advice and should not be used as an alternative to professional health care. If you have a particular medical problem, please consult a healthcare professional.

Except as permitted under the Copyright Act 1968, this publication or any part of it may not be reproduced, altered, adapted, stored and/or distributed in any form or by any means without the prior written permission of Healthdirect Australia.