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Pregnancy at week 21

On this page

  • Your baby
  • Your body
  • Things to remember
  • Resources and support

Your baby

Most women start to feel their baby moving between 16 and 24 weeks of pregnancy. The first sensations you feel may be a fluttering (like 'butterflies in your tummy'), swishing, rolling or tumbling sensation or a tiny kick. These early sensations are often called 'quickening'.

By now, your baby's arms and legs have grown and are looking more in proportion to the rest of their body. There is also some soft hair growing on your baby's head. Your baby's reproductive organs are still developing but by now, if your baby is female, their uterus is formed and if your baby is male, their testicles are formed.

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Your body

Your growing uterus might be putting pressure on your stomach, leading to heartburn or indigestion. This is very common in pregnancy. You can improve how you feel by eating smaller meals, avoiding foods that you know trigger your symptoms, and by raising your head when you lie down.

If your heartburn is very bad and it's not helped by lifestyle changes or medications from the pharmacy, then mention it to your doctor or midwife. It could be the sign of something more serious such as pre-eclampsia.

Other common pregnancy discomforts you might have at this time include bloating and gas, as well as changes to your appetite. Try to eat small, nutritious meals as part of a healthy diet.

Things to remember

The second trimester is a good time to travel since you may not be able to do so later in your pregnancy. If you decide to go away, you will need to take a few precautions.

If you have a normal, healthy pregnancy, there's no reason why you cannot fly up until 28 weeks into the pregnancy. Always check with the airline and your travel insurer before you go. You are more at risk of deep vein thrombosis (DVT) (Opens in new tab) when you're pregnant, so it's important to keep walking around the plane and to wear compression stockings on long flights.

If you're driving, it's very important - as well as required by law — to wear a seatbelt in the car. Put the lap part underneath your bump.

Always take care with what you eat and drink while you're pregnant, especially if you're overseas. If in doubt, drink bottled water and make sure you stay well hydrated in hot climates. See a doctor straight away if you get sick.

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
Your pregnancy at week 20
Your pregnancy at week 22

Speak to a maternal child health nurse

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

  • Raising Children Network — Pregnancy week-by-week (Opens in new tab)
  • Safer Baby — Your baby's movements matter (Opens in new tab)
  • Smartraveller — Advice for pregnant travellers (Opens in new tab)
  • Perinatology.com — Fetal Development (Opens in new tab)
  • NSW Health — Having a baby (Opens in new tab)
  • Department of Health and Aged Care — Australian Pregnancy Care Guidelines (Opens in new tab)

Find out how we develop and review our content.


Last reviewed: August 2023

Need more information?

These trusted information partners have more on this topic.

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.
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The Fourth Trimester | Ausmed

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First trimester: pregnancy week by week | Raising Children Network

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Concerns for parents about having a second child | COPE

Parents can have a number of concerns about having a second child, as pregnancy, birth and your parenting experience may be quite different .
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Learn more on COPE website

Third 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 third trimester.
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Effects Of Smoking, Second Hand Smoke & How To Quit | Your Room

Tobacco is a legal drug which has many short and long term side effects. Read about the effects of smoking, breathing second hand smoke and how to quit.
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Women and stroke | Better Health Channel

Stroke is the second biggest killer of Australian women and kills more women than breast cancer.
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Second-hand smoke and your health

Information on passive smoking and your health.
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Learn more on WA Health website

Pregnancy Acne - Acne During Pregnancy - All About Acne

Not all pregnancies lead to acne but if you have hormonal acne, it is likely to flare during the first trimester of your pregnancy.
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Passive smoking | Better Health Channel

Passive smoking means breathing other people's second-hand tobacco smoke. Passive smoking increases the risk of serious illness in both children and adults.
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  • Pregnancy at week 14
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  • Pregnancy at week 17

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