16 wks

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