Your baby measures a whopping 5 - 6 ounces now, and it may feel like he or she couldn't possibly get any bigger, but think again! As heavy as your belly feels now, it'll be even heavier by the time your due date arrives, as most babies are born between 6 and 8 lbs.
This week, your baby's soft cartilage starts to firm up and soon he or she will have hard bones which will help protect from damage from all those falls and tumbles that will happen during the toddling stage. The only area that doesn't harden completely before birth is the skull, which remains malleable in order to squeeze through the birth canal without causing too much damage to your private parts.
Your baby's brain is really starting to function well, and is controlling more and more of the body. Most actions are now deliberate, especially reaching and grabbing, and boy does that baby have a strong grip! You'll see this in your newborn when you put your finger to his or her hand and can't retract it for at least an hour! The heart is also regulated by the brain now, creating a steady beat that's roughly twice as fast as your own.
Sweat glands are starting to form all over the body, although there won't be any sweating going on in the womb. Sweating occurs as a way to cool the body, but the temperature inside your uterus remains pretty much constant and stable throughout the pregnancy so sweating simply isn't needed. Your baby will be producing fluids, though, as the amniotic fluid that's sucked in and swallowed is urinated back out.