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Pregnancy at week 20
Your baby
Your baby now has fingerprints, permanent teeth in their gums underneath their baby teeth and, if it's a girl, there are already eggs in the ovaries. Cartilage throughout their body is turning into bone and their bone marrow is starting to make blood cells.
Your baby's ears haven't finished developing yet but they can hear sounds from outside your uterus.
Your baby is also starting to build up their stores of brown fat (also known as adipose tissue) and will continue to form more of this tissue as they grow and develop in your uterus. Good stores of brown fat will help your baby to keep warm after they are born.
Your body
Congratulations, you are now half-way through your pregnancy. The top of your uterus, called the fundus, is usually now roughly level with your belly button. Your doctor or midwife will measure your belly each time you have a check up. Your belly measurements should measure about the same in centimetres as the number of weeks you are pregnant. For example, at 20 weeks, your belly should measure 20cm.
As your uterus takes up more room, there is less space for your other organs, including your heart and lungs. This might make you feel breathless from time to time, especially when you lie on your back, try lying on your side with a pillow to support you.
You may not have heard of your round ligaments before, but they have an important role to play during pregnancy. They are on either side of your uterus (Opens in new tab) and work to support your uterus in the pelvis. As your uterus stretches during pregnancy, your round ligaments stretch too. This can cause aching, cramping, or even a sharp, stabbing feeling. You can help ease this pain by doing gentle stretches, moving slowly and wearing an elastic belly band for extra support.
While round ligament pain is quite common, it can be alarming to notice this feeling in your abdomen during pregnancy, and there are other pregnancy complications that may cause these sensations too. If you're worried about pain or if you have any questions, it's always best to talk to your doctor or midwife to be sure.
Things to remember
You might have trouble fitting into your normal clothes at this point. But, you don't have to spend a lot of money on maternity clothes. Look through your wardrobe for loose fitting tops, or borrow from your partner or friends. You can buy an'expander' that makes your normal pants and skirts larger so you can keep wearing them through your pregnancy.
You don't have to wear a special bra while you're pregnant, though underwire bras are not recommended during pregnancy. Many women find a maternity bra more comfortable. Bras designed for pregnancy can also be used while you're breastfeeding. It's a good idea to have a maternity bra professionally fitted, if you haven't done so already.
Your midwife or doctor will likely have discussed your option to have a morphology scan by now. This ultrasound can be done anytime between about 18 and 22 weeks of pregnancy and looks at your baby's body structures and organs to check that everything is developing as expected.
You can talk to your doctor or midwife about any other recommended tests during your pregnancy.
Resources and support
Speak to your doctor, midwife or obstetrician if you have questions about your pregnancy.
Pregnancy, Birth and Baby also has more information on:
- maternity care in Australia
- having a healthy pregnancy
- exploring the anatomy of pregnancy and birth
- checkups, screenings, scans and tests you can have during your pregnancy
- common conditions you might experience during your pregnancy
- looking after your mental health and wellbeing
Find out how we develop and review our content.
Last reviewed: August 2023
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