On my 16 weeks Pregnancy

At 4 1/2 inches long (head to bottom) and 3 1/2 ounces, my baby is about the size of an avocado. In the next three weeks, he'll go through a tremendous growth spurt, though, doubling his weight and adding inches to his length. His lower limbs are much more developed now. His head is more erect than it has been, and his eyes have moved toward the front of his head. My baby's ears are close to their final position, too. Some of his more advanced body systems are working, including his circulatory system and urinary tract. His heart is now pumping about 25 quarts of blood each day, circulating his total blood volume through his body many times. (By the end of my pregnancy, this will increase to about 190 quarts.) The patterning of his scalp has begun, though his hair isn't recognizable yet. Although closed, his eyes are moving (slowly), and he's even started growing toenails.

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