How your baby's growing:Your baby's sensory development is exploding! Her brain is designating specialized areas for smell, taste, hearing, vision, and touch. Some research suggests that she may be able to hear your voice now, so don't be shy about reading aloud, talking to her, or singing a happy tune if the mood strikes you.
Your baby weighs about 8 1/2 ounces and measures 6 inches, head to bottom — about the size of a large heirloom tomato. Her arms and legs are in the right proportions to each other and the rest of her body now. Her kidneys continue to make urine and the hair on her scalp is sprouting. A waxy protective coating called the vernix caseosa is forming on her skin to prevent it from pickling in the amniotic fluid.
From: Baby Center 19 weeks