19 weeks.

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.

How your life's changing:
Think you're big now? You'll start growing even faster in the weeks to come. As a result, you may notice some achiness in your lower abdomen or even an occasional brief, stabbing pain on one or both sides — especially when you shift position or at the end of an active day. Most likely, this is round ligament pain. The ligaments that support your uterus are stretching to accommodate its increasing weight. This is nothing to be alarmed about, but call your practitioner if the pain continues even when you're resting or becomes severe.

You may be noticing some skin changes, too. Are the palms of your hands red? Nothing to worry about — it's from the extra estrogen. You may also have patches of darkened skin caused by a temporary increase in pigment. When these darker patches appear on your upper lip, cheeks, and forehead, they're called chloasma, or the "mask of pregnancy." You may also notice some darkening of your nipples, freckles, scars, underarms, inner thighs, and vulva. That darkened line running from your belly button to your pubic bone is called the linea nigra, or "dark line."

These darkened spots will probably fade shortly after delivery. In the meantime, protect yourself from the sun, which intensifies the pigment changes. Cover up, wear a brimmed hat, and use sunscreen when you're outdoors. And if you're self-conscious about your "mask," a little concealing makeup can work wonders.

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