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Second trimester · roughly month 5 · about 19 weeks to go

21 weeks pregnant

Everything Hello Belly has for week 21 — how your baby is developing, what your body is doing, and the small things that are easier to know in advance.

Illustration of a pregnant woman at week 21

Your baby at 21 weeks

21–22 weeks

Look, how big and beautiful became the baby! Active, restless baby. The baby who has learned to swallow and distinguish the taste of broccoli from chocolate (by the way, it depends on you and your diet that he will like more!). The baby who raised and strengthened all the bones (yes, that's why his jerks became much more tangible). The baby who is intensely engaged in a particular kind of sport: shake your Mommy when she goes to bed. By the way, in this case, you can use some “sleepy” techniques for newborns: talk calmly with the baby, stroke your stomach, sing a lullaby or turn on quiet music.

And notice, there are more wrinkles on the little body now! Your baby grows both in length and in width, eating up intently the fat layer (what if winter is coming?). But though he kind of eats well, grows, collects fat, his head is still disproportionately large. But trust, there is a good reason: now your baby weighs not more than 1 lb, and the brain can reach 0.1 lb — just imagine, the brain can be more than 10% of his total mass! Therefore, every time you think that he does not understand anything, remember that 10%. He understands everything and feels everything.

This week's open tip

Read it in full right here — no account needed.

  • No sleep for you! — week 21 of pregnancy

    No sleep for you!

    This week, your baby is constantly letting you know she’s there with all of her kicking! She has grown significantly, became stronger, and is now the size of a large banana — up to 11 inches (27 cm).

    Read the full tip →

Also in the app this week

6 more tips for week 21 — a new one arrives each day inside Hello Belly.

Following week 21 in real time?

Pick your date and every page becomes yours — a new tip each day, for the week you're actually in.

Illustration of a pregnant woman at week 16Week 16 · Second trimester

Due around week 21?

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