Our baby is 5 inches long and a little bigger than an avocado... I've gotten a little bigger than that! :)
My fave baby website (Baby Center) says: "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 he's around 5 inches long from head to bottom. He can move his joints, and his sweat glands are starting to develop."