21 Weeks Pregnant
Your baby is the size of a

You're officially in the midst of your second trimester and have reached the 21-week mark of your pregnancy. By now, you've probably experienced a range of changes in your body and emotions. From feeling your baby's first wriggles to potentially finding out the gender, there's a lot to look forward to at this stage. We’ll cover everything you need to know about being 21 weeks pregnant, from your baby's development to symptoms you may experience, and what to expect in the coming weeks.
Highlights at 21 Weeks Pregnant
Below we’ve highlighted some of the ways your baby is growing and changing, and how you might be feeling at 21 weeks pregnant:
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21 Weeks Pregnant: Your Baby’s Development
Here are some of the exciting developmental steps your baby is making this week:
How Many Months Is 21 Weeks Pregnant?
Now that you're at 21 weeks pregnant, how does that translate into months? Although pregnancy can be measured in various ways, at 21 weeks, you’re most often considered five months pregnant.
It’s also common to wonder how many weeks are left when you’re at 21 weeks pregnant. Although it’s difficult to know the exact day your baby will arrive, full term is usually around 40 weeks. You can get an estimate by using our Due Date Calculator.
How Big Is a Baby at 21 Weeks Pregnant?
When you’re 21 weeks pregnant, your baby’s size is roughly the same as a banana. Your little banana is growing quickly and they’re likely over 15 centimetres long and weigh about 300 grams!
Your Baby: What Does 21 Weeks Pregnant Look Like?
This illustration can help you envisage what your little one may look like inside your pregnancy bump at 21 weeks:
Your Body at 21 Weeks Pregnant
You may have had some heartburn and indigestion earlier in the first trimester, but around 21 weeks pregnant, as your baby grows your uterus gets larger and may start pushing up against your stomach. This can cause you to have heartburn more frequently.
Around this time, your pregnancy hormones may also cause hot flashes, and the extra weight gain can cause some aches and pains now and in the coming weeks.
21 Weeks Pregnant: Your Symptoms
At 21 weeks pregnant, you may be experiencing some of the following symptoms:
How Big Is a Pregnant Belly at 21 Weeks?
Every pregnancy is unique, but at 21 weeks pregnant your belly bump might be quite noticeable, as your baby and uterus continue to grow. Your uterus might reach your navel by now and may also be pushing up against your stomach.
As you move past quickening—your baby’s first movements—it will be exciting to feel those fetal movements getting stronger at 21 weeks pregnant and in the coming weeks—prepare to feel some little jabs and kicks.
What Does 21 Weeks Pregnant Look Like?
For a better idea of what your belly might look like around 21 weeks pregnant, check out the image below.
21 Weeks Pregnant: Things to Consider
Your pregnancy journey will bring many lifestyle changes along the way. Check out some helpful things to consider at 21 weeks pregnant:
Tip for Partners |
21 Weeks Pregnant: Consult Your Healthcare Provider
With pregnancy comes many questions and concerns. Remember that your healthcare provider is always there to guide you along the way. Here are some common questions at 21 weeks pregnant:
FAQS AT A GLANCE
Despite the different ways of dividing the 40 weeks of pregnancy into months, likely you're still in your fifth month of pregnancy by the time you reach 21 weeks.
In this article, you can discover more information on the size of your baby, belly, and some helpful pregnancy tips for you when you’re 21 weeks pregnant.
21 Weeks Pregnant: Your Checklist
As you hit the halfway point in your pregnancy, consider some of the following to-dos:
□ Get a footrest to elevate your feet slightly whenever you sit.
□ Treat yourself to warm baths to help relieve back pain.
□ If you haven’t done so already, sign up for a childbirth class.
□ Make sure your baby registry is done, especially if your baby shower is happening soon.
□ It may be time for your partner to start looking into paternity leave if they haven't done this already.
21 weeks pregnant - checklist
How We Wrote This Article The information in this article is based on the expert advice found in trusted medical and government sources, such as the American Academy of Pediatrics and the American College of Obstetricians and Gynecologists. You can find a full list of sources used for this article below. The content on this page should not replace professional medical advice. Always consult medical professionals for full diagnosis and treatment.
- American College of Obstetricians and Gynecologists. Your Pregnancy and Childbirth: Month to Month, 7th ed. (Washington, DC: American College of Obstetricians and Gynecologists, 2021).
- American College of Obstetricians and Gynecologists. Your Pregnancy and Childbirth: Month to Month, 6th ed. (Washington, DC: American College of Obstetricians and Gynecologists, 2015).
- Mayo Clinic. Guide to a Healthy Pregnancy, 2nd ed. (Rochester, MN: Mayo Clinic Press, 2018).
- Cleveland Clinic. “Braxton Hicks.”
- Cleveland Clinic. “Fetal Development Stages of Growth.”
- Mayo Clinic. “Pregnancy Week by Week.”
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