The Baby's Exact Size
Your baby is growing very quickly. From crown to rump, she measures four inches long at the begining of this week, and weighs about two and a half ounces. By the end of the week, she will gain an entire ounce and will have grown to a full 4.6 inches long. Your amazing body is gearing tons of energy toward facilitating this rapid growth, so be sure that you're getting adequate sleep and rest.
A 15-Week-Old Fetus is the Size of...
Numbers don't always cut it when you're trying to envision what your baby looks like. At 15 weeks gestation, your baby will be about the same size as a navel orange, an apple, or an avocado. She's curled up in the fetal position, but, if you were measure her from crown to toe, she'd be about as long as a ballpoint pen. Her little feet are about the same size as your pinky-nail.
What the Baby Looks Like
Your baby is now very clearly a boy or a girl, and she is looking more and more like a real baby as each day passes. Her legs are now longer than her arms, and all of her joints work. She has several reflexes and will grimace or jump in response to loud noises or a light shined on your belly. Her eyelids are still shut, but she's making all kinds of facial expressions, including "crying" and squinting. You'll reach full-term before you know it!