Being 21 weeks pregnant: What to expect + Pregnancy tips

Congratulations—you’re 21 weeks pregnant and well into your second trimester! After 140 days, you’re about to cross another pregnancy milestone. But what should you know when you’re 21 weeks pregnant? Keep reading as we look at all the need to know details.

Your baby is now about the size of a carrot, weighing around 350 grams, and their movements might feel stronger and more consistent. Previously, your baby was measured from the top of their head to their buttock (crown to rump). However, this week, they’ve uncurled their leg enough to be measured from head to heel (crown to heel). They are about 27cm and weigh approximately 398g. Their digestive system is also developing, practising swallowing and absorbing nutrients, which is an exciting milestone.

Here’s a look at your baby at 21 weeks, your body after five months, and how to prepare for the final stretch. You’re officially in the second half of your pregnancy – 21 weeks down, 19 weeks to go! 

As your bump grows, you may experience backaches or leg cramps, so staying active with light exercises and practising good posture can help. Hydration, balanced nutrition, and some well-deserved rest will keep you feeling your best. Let’s explore what to expect this week and some pregnancy tips to keep you on track.

Your baby at 21 weeks of pregnancy

Your baby is now roughly half the size it will be at birth. They are continuing to grow and prepare for life outside of the womb. Here are the key developments about your fetus at 21 weeks of pregnancy. 

Fetal movement

Babies at 21 weeks have legs and arms in proportion to the rest of their body. The neurons between their brain and muscles are also now connected. This is why you will start to feel more movement. In the coming weeks, what started as occasional kicks and thumps will eventually lead to what feels like a full-out dance party in your belly.

Eyelids

Your baby’s eyelids are now beginning to separate. Although they can already “see” light, their eyelids have been sealed since around week 11. At the end of your second trimester, around week 26, your baby’s eyes can open and close.  

Sleep cycles

The fetus, at 21 weeks, is starting to develop a sleep cycle. You may not believe it with all the kicking going on, but they are getting about as many hours of sleep as a newborn baby. 

Your body at 21 weeks pregnant 

Most pregnant people consider the second trimester to be the most comfortable. You’re not yet feeling the full physical demands of a growing baby on your body, and hopefully, your morning sickness has subsided. 

Although pregnancy at 21 weeks is different for everyone, here are some of the most common symptoms. 

• Varicose veins. Another not-so-lovely 21-week pregnancy side effect is swollen blood vessels called varicose veins. These can result from your body’s increased levels of progesterone during pregnancy. The pressure of the uterus on the inferior vena cava (the large vein that transfers blood from the lower half of your body to your heart) can also cause varicose veins to appear. These are different from spider veins in that they make a slight purple lump just above the skin. They’re mostly harmless and should go away after giving birth.

• Baby body. At week 21 of pregnancy, you may have gained between 5 and 6 kg. You are probably also starting to notice a more pronounced baby bump.
  Now is the perfect time to embrace your extra weight gain and recognize all the important purposes it’s serving. Not only are you keeping your baby alive, but you’re also ensuring they grow strong and healthy.

• Stretch marks. As your baby grows and you put on weight, you may start to notice stretch marks appearing on your body. They can pop up on your stomach, breasts, butt, hips, and thighs. There aren’t any proven ways to prevent getting them; experts believe it’s mostly down to genetics. If your mom had stretch marks during pregnancy, you’re a likely candidate. Gaining weight too fast can also spur stretch marks – another reason why being conscious about your health and nutrition during pregnancy is so important.

• Heartburn. It’s totally normal to experience heartburn, also called indigestion or acid reflux, during pregnancy at 21 weeks. The valve between your stomach and the oesophagus becomes relaxed due to pregnancy hormones. This can cause some of your stomach acid to transfer to your oesophagus. Certain foods are known to trigger heartburn, such as citrus, caffeine, spicy foods, and greasy foods.

• Headaches. Mild headaches during the 21st week of pregnancy are common. They are most often caused by dehydration, stress, or hormones. Changes in your vision can also cause headaches, like switching between glasses or contact lenses throughout the day. 

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Taking care of yourself during week 21 of pregnancy

Focusing on your well-being benefits both you and your baby. Here are some tips and helpful reminders on how to best take care of yourself during pregnancy week 21. 

• Pay attention to your iron levels. A common vitamin deficiency experienced by women during pregnancy is low levels of iron. Make sure you’re including plenty of iron-rich foods in your diet, like beans, lentils, spinach, dried apricots, iron-fortified cereals, and red meat. Or, take a supplement. Pairing these foods with vitamin C also allows your body to better absorb iron. Caffeinated drinks, like coffee and tea, can inhibit the absorption of iron.

• Practice low-impact exercises. Pregnant women at 21 weeks become more susceptible to injury. Factors such as weight gain, a heavier front load, and a changing body shape make you less stable. Also, the hormone relaxin causes your ligaments to loosen. As your 21-week fetus continues to grow, low-impact exercises, such as pregnancy-safe yoga, swimming, and walking, are great options for keeping fit and healthy.

• Rest your feet. Spending too much time on your feet can cause pregnancy symptoms such as backaches, varicose veins, and swollen feet and legs to worsen. Try to avoid standing for long periods of time, especially if you’re wearing uncomfortable clothing or shoes. 

• Nourish your body. Feeling good comes from within. A balanced diet can ward off unpleasant pregnancy symptoms and is linked to good brain development in babies. Remember that food is medicine, and making the right choices now will only benefit you and your baby in the long run.

• Make time for socialising. Having a support system during pregnancy can do wonders for your well-being. Simple, regular interactions, like Facetime calls with family members or date nights with your partner, can help promote emotional health. 

FAQs about 21 weeks of pregnancy

What is my baby doing at 21 weeks in the womb?

Week 21 of pregnancy is an exciting time for you and your growing bundle of joy. These seven days involve a lot more motion as the fetus starts to groove around. It can involve some punching and jerking, but that’s normal, and this period is called the quickening.

What should I do at 21 weeks pregnant?

As your pregnancy moves along, it’s important to remain as active as possible during your 21st week. It’s best to speak to your healthcare provider about what exercises you can do, but generally, things like walking, prenatal yoga, and swimming should do the trick.

What position is a baby in at 21 weeks?

Starting in week 21 of pregnancy and lasting till your 24th week, your baby is going to be changing position a lot as it’s still tiny enough to practice its agility. This means it can position itself head down, feet down, or even sideways.

How big is my baby at 21 weeks?

Your baby is roughly the size of a carrot, measuring around 18–20 cm from head to bottom. They’re continuing to gain weight and develop essential body systems.

What developments are happening with the baby now?

Your baby’s digestive system is evolving, and they may begin swallowing amniotic fluid. Their sense of touch is also improving, and they can start to feel sensations within the womb.

What pregnancy symptoms might I notice at 21 weeks?

Many women experience a growing bump, mild swelling in the feet or ankles, and possible back or pelvic discomfort. Heartburn, indigestion, and occasional breathlessness can also continue.

Can I feel more baby movements at 21 weeks?

Yes, you’re likely to feel more pronounced kicks or rolls. You may also notice your baby’s active and quiet periods throughout the day. If you have concerns about movement, consult your healthcare provider.

Is it normal to gain weight around this time?

Yes, steady weight gain is typical during the second trimester. The amount varies for each individual, so discuss any concerns with your midwife or doctor for personalised guidance.

How can I manage back pain or pelvic discomfort?

Try gentle exercises like prenatal yoga, maintain good posture, and use a pregnancy pillow for additional support while sleeping. If the pain is severe or persistent, seek medical advice.

What should I focus on in my diet at 21 weeks pregnant?

Continue eating nutrient-dense foods, including fruits, vegetables, whole grains, lean proteins, and dairy (or alternatives). Ensure adequate intake of iron, calcium, folic acid, and other vital nutrients.

Can I still exercise safely?

Moderate, low-impact exercise such as walking, swimming, or prenatal yoga remains beneficial if you have no medical complications. Always follow the advice of your healthcare provider regarding activity levels.

How can I cope with stress or mood swings at this stage?

Hormonal changes and life adjustments can cause emotional fluctuations. Try relaxation techniques like breathing exercises or gentle stretching, and confide in a trusted friend, partner, or professional if needed.

Do I need any specific tests or scans at 21 weeks?

Many women have a detailed anatomy scan between 18 and 22 weeks. If you haven’t yet, your healthcare provider may schedule a scan to check your baby’s development and screen for any concerns.

What about heartburn and indigestion?

As your uterus expands, it can push against your stomach, causing heartburn or indigestion. Eating smaller meals, avoiding spicy or acidic foods, and waiting a while after eating before lying down may help.

When should I contact my healthcare provider?

If you experience severe pain, heavy bleeding, a significant decrease in baby movements, or any other unsettling symptoms, reach out to your midwife or doctor immediately. They are there to support your health and wellbeing.

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