The Inside Story: Your Baby in Week Thirty-One

He's really moving now -- from stronger kicks to hiccups that could wake you up at night.

fetal development SebastianKaulitzki/

You may notice that your baby moves more when you talk to him. You'll probably start feeling different kicks now as his body continues to grow, but the kicks you do feel will be harder. They might even hurt, especially if he's practicing karate chops on your groin.

Your baby may weigh 3 1/2 pounds this week, and he should be 16 inches in length. His belly is Buddha-like, round and hard because his liver is busily producing red blood cells. Some babies have a full head of hair by the 31st week of pregnancy, while others are bald as eggs. It's common for babies to hiccup at this stage and for the hiccups to be strong enough to wake you in the middle of the night.

If you want to have some fun, shine a light on your stomach to see if your baby changes his movements. (If he doesn't, he might be napping; try it again in a few hours.) You can also press against your abdomen to see if he answers you with a kick. Or rest a book on your belly and marvel when he objects to the encroachment on his home turf by kicking the book right off your stomach.

    Originally published in You & Your Baby: Pregnancy.

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