16 & 17 Weeks - From avocado to turnip

How your baby's growing @ 17 weeks:
Your baby's skeleton is changing from soft cartilage to bone, and the umbilical cord — her lifeline to the placenta — is growing stronger and thicker. Your baby weighs 5 ounces now (about as much as a turnip), and she's around 5 inches long from head to bottom. She can move her joints, and her sweat glands are starting to develop.

He's adding fat stores that will keep him warm and cozy after he's born. Your baby's weight will increase approximately six times over the next four weeks. Your baby is hard at work honing his sucking and swallowing reflexes—all the better for eating that 2 AM (and 5 AM, and 8 AM ...) meal in a few months! The finger- and toenails are beginning to grow from their nail beds, which would explain why he'll need them trimmed almost as soon as he's born!

Your baby weighs nearly 5 ounces and is a little over 5 inches long—about the size of a baked potato (load on the butter and sour cream, please).

How your baby's growing @ 16 weeks:
Get ready for a growth spurt. In the next few weeks, your baby will double his weight and add inches to his length. Right now, he's about the size of an avocado: 4 1/2 inches long (head to rump) and 3 1/2 ounces. His legs are much more developed, his head is more erect than it has been, and his eyes have moved closer to the front of his head. His ears are close to their final position, too. The patterning of his scalp has begun, though his locks aren't recognizable yet. He's even started growing toenails. And there's a lot happening inside as well. For example, his heart is now pumping about 25 quarts of blood each day, and this amount will continue to increase as your baby continues to develop.