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Trimester 2

Pregnancy Week 21

Your baby is about the size of a carrot

Your baby, or fetus, is now about 27.4 cm long from head to heel and weighs around 399 grams—roughly the size of a carrot.

Baby development

What does my baby look like?

This week your baby is roughly the size of a carrot. You're now in the fifth month of your pregnancy.

Your baby now weighs more than the placenta. The placenta delivers nutrients and oxygen to your baby and helps carry away waste. It keeps growing throughout pregnancy so it can keep doing this important job.

Around this time, your baby's body is covered with fine, soft hair called "lanugo." This hair usually falls away for the most part before birth. Your baby also continues to develop hair and eyebrows.

Your baby can now begin to hear sounds from outside the womb—and your voice is one of them.

Baby is moving and sleeping

Your baby still has room to move around in the womb, so you may feel turning, stretching, and the occasional somersault.

Your baby also sleeps for long stretches. A pattern of sleeping and waking is becoming more and more defined inside the womb.

Baby's taste buds are developing

Your baby swallows a little amniotic fluid each day. This isn't just practice for swallowing and digestion—it's also important for developing the sense of taste.

The flavor of the amniotic fluid can change depending on the foods you eat. Babies who are exposed to certain flavors in the womb may be more open to those same flavors after birth.

The senses of smell and taste also play a role in your baby's early bonding and feeding after birth.

Baby is becoming more coordinated

Around this time, the arms and legs become more proportional. The connections between the brain and muscles are developing, and some of the cartilage in the body keeps turning into bone.

All of this gives your baby more control over their limb movements. That's why you may feel kicks, stretches, and other movements more distinctly.

Your body and changes

What's happening in my body?

As your belly grows, your center of gravity can shift. This may leave you feeling a bit off-balance or clumsy. To lower your risk of falling, it helps to move slowly and be extra careful on slippery or uneven surfaces.

If you do have a fall, try not to panic—but you should let your doctor know.

Your baby's movements may feel stronger at night. Once you settle down to rest, your baby may become more active.

Varicose veins and circulation

As pregnancy progresses, the weight of the uterus can put more pressure on the veins in your legs. Rising progesterone levels can also cause the walls of your veins to relax. Because of this, varicose veins or spider veins may become more noticeable.

Some steps that may help reduce varicose veins include:

  • moving regularly
  • not staying still for long periods
  • raising your feet whenever you can
  • not crossing your legs while sitting
  • wearing compression stockings if needed

Gums and oral health

About half of expectant mothers can develop pregnancy gingivitis. You might notice it as bleeding and tenderness in your gums when you brush or floss.

It's important to brush regularly, floss, and pay attention to your oral hygiene. Seeing the dentist during pregnancy is generally safe; don't skip your regular dental checkups or any necessary treatment.

Braxton Hicks contractions

Braxton Hicks contractions are occasional, irregular, and usually painless "practice" contractions. Some women start to feel them around this time, while others never notice them at all.

These contractions are more likely to be felt in situations like:

  • at the end of the day
  • when you're dehydrated
  • when your bladder is full
  • during or after physical activity

Braxton Hicks contractions are usually harmless. But if you have regular contractions or think you may be seeing signs of preterm labor, you should contact your doctor.

Heartburn

Heartburn can feel like a burning sensation that spreads up from below your breastbone toward your throat. It's common in pregnancy because of hormonal and physical changes. It's usually not dangerous, but it can be uncomfortable.

Weight gain and swelling

During this stage, you may be gaining about half a kilogram a week. That said, the ideal amount of weight gain varies depending on your personal health.

As the weeks go by, you may notice mild swelling in your fingers and hands. If your rings feel tight, it may be a good idea to take them off. If there's more than moderate or sudden swelling in your hands, talk to your doctor.

Sleep and fatigue

If your sleep is broken up at night, taking a short rest whenever you get the chance during the day can feel good.

Whooping cough vaccine

The whooping cough vaccine usually comes up around this stage of pregnancy. It may be recommended around week 20 and can be given from week 16 through week 32. If you haven't had it yet, you should talk with your doctor.

Symptoms

Symptoms you may notice this week

Pregnancy symptoms you may notice this week can include:

  • fatigue and trouble sleeping
  • stretch marks
  • swollen, bleeding gums
  • round ligament pain caused by your expanding uterus
  • hemorrhoids
  • back pain
  • nosebleeds
  • indigestion and heartburn
  • bloating and constipation
  • leg cramps
  • dizziness
  • swollen hands and feet
  • urinary tract infections
  • vaginal infections
  • darkening skin or brown patches on your face
  • oilier, more acne-prone skin
  • thicker, shinier hair

Some familiar symptoms from earlier weeks may also continue:

  • mood swings
  • morning sickness
  • pregnancy cravings
  • tender or leaking breasts
  • milky white vaginal discharge
  • light spotting

Any bleeding should be evaluated by a medical professional.

Changes in your hair

During pregnancy, hormones can slow down hair shedding, which is why your hair may look fuller or thicker. After birth, you may shed more hair; this is usually temporary.

Melasma

During this stage, you may notice dark patches of skin called melasma, or chloasma. This usually shows up on the upper lip, cheeks, and forehead. Sunlight can make these patches darker, so it's important to protect yourself from the sun.

Headache

Mild headaches are common in pregnancy. But if you have the following symptoms, you should see your doctor right away:

  • a severe headache
  • blurred vision or flashing lights
  • pain just below your ribs
  • vomiting
  • sudden swelling in your face, hands, feet, or ankles

These symptoms can be linked to preeclampsia.

Nutrition

What to eat to boost your iron levels

Anemia is common in pregnancy. Red blood cells carry oxygen through your body and to your baby. A healthy, balanced diet can support your iron intake.

Try to eat iron-rich foods regularly:

  • leafy green vegetables like broccoli and spinach
  • iron-fortified breakfast cereals

Cut back on junk food

A diet with plenty of fresh fruits and vegetables can give you steadier energy. Eating well matters for both mother and baby.

You might prioritize:

  • 5 servings of fruits and vegetables a day
  • whole-grain options
  • low-fat options
  • low-sugar options

Simple food swaps

Some simple, healthy meal alternatives could be:

  • an easy pizza calzone
  • chicken and banana korma
  • homemade fish and chips

Vegan or vegetarian eating

A vegan or vegetarian diet is possible during pregnancy as long as it's balanced and includes all the food groups. Getting enough iron and vitamin B12 is especially important.

Tips and exercise

Time to take action

Pregnancy can be stressful for some expectant mothers. If something unexpected has come up in your screening results, it's important to talk through your options with your doctor.

Walking and bowel movements

Physical activity like a brisk walk can help you cope with constipation. Drinking enough water and choosing high-fiber foods can help, too.

Circulation and movement in pregnancy

Blood circulation increases during pregnancy, which can lead to a feeling of heaviness, swelling, or discomfort in your legs. Taking short rests during the day and raising your feet can help.

Good to know

The second half of pregnancy

As you enter the second half of your pregnancy, your baby keeps preparing for basic skills like sucking and breathing.

Sex drive

Your sex drive can go up or down during pregnancy—it varies from person to person. Unless your doctor tells you otherwise, having sex during pregnancy usually doesn't harm the baby.

Thinking about your birth options

You can start thinking about your birth plans around this time. You can talk with your doctor about things like where you'd like to give birth, who you'd like with you, and what kind of birth experience you want.

Stretch marks and skin changes

Stretch marks may start to become more noticeable during this stage. They usually appear around the belly, breasts, hips, thighs, and buttocks. They can't be completely prevented, but keeping your skin moisturized can help reduce dryness and itching.

Anxiety

It's normal to feel anxious or have mixed emotions during this stage. As pregnancy progresses, thoughts about motherhood, birth, and the future can intensify. Talking about these feelings with your partner or people you trust can help.

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