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Guide to Being 18 Weeks Pregnant

What's Going On in Your Body

Length: About 5.5 inches. Weight: About 6 ounces. Bones: Starting to harden.

Oh, the things that are transpiring in your uterus. Eyes are sensing light through thin eyelids, ears are hearing music you play in the car, and the skeleton is starting to ossify into what we know as bone.

All that, and:

  • Increasing movement -- Baby is now kicking, punching, yawning, sucking, rolling around and stretching like never before.
  • Facial expressions -- Facial muscles are practicing the expressions you'll notice immediately at birth, like pursed lips, a tiny frown and crinkled eyes.
  • Taste buds -- They're now developed enough to distinguish between the bitterness of your morning decaf coffee and the sweetness of your late-night chocolate treat.
  • Nerve protection -- A coating called myelin is forming around delicate nerves.
  • Gender development -- Girls are well on their way to having the sex organs they'll be born with, like properly positioned fallopian tubes. Theoretically, you could see a vagina or penis at an ultrasound this week, but only if the positioning is just right (and it often isn't).
  • Proportionality -- No longer shockingly big-headed, your baby's body is catching up in length and size.

And as all this goes on deep inside your uterine walls, your partner can put some attention toward some perhaps less miraculous but still quite significant issues for both of you …