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Second trimester · roughly month 5 · about 22 weeks to go

18 weeks pregnant

Everything Hello Belly has for week 18 — 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 18

Your baby at 18 weeks

17–18 weeks

Just look at your baby: he’s grown so big! While constantly swimming in his environment, which totally involves his muscular system and enhances brain activity, he squeezes and unclenches his fists. So don’t mess around with this guy! (Though he still fits entirely in your palm).

It’s not just he grew up, he also became much more massy. Thanks to the first fat layer, which began to form under the skin. By the way, the skin has become thicker, it consists of several layers and is covered with creamy white grease that protects the baby. And he already has hair on his head. And crotches and cilia on his face. Cutie, in a word.

The baby seems to be so small and naked, but he has already become more independent of you: the immune system has formed. Now your infections are not so terrible for him (but for sure this is not a reason to fall ill right away!)

This week's open tip

Read it in full right here — no account needed.

  • Hmm... Obviously a boy? — week 18 of pregnancy

    Hmm... Obviously a boy?

    Your baby has grown up again and this week has become the size of a bell pepper. She continues to jerk her hands and feet, and if you still do not feel it, then you will very soon.

    Read the full tip →

Also in the app this week

6 more tips for week 18 — a new one arrives each day inside Hello Belly.

Following week 18 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 18?

Tell us once — every page becomes yours.

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