This week marks a milestone for your baby-to-be—and for you. She's developed to the point where she's no longer an embryo, but a fetus. She's now approaching two inches in length. If you could see her, you'd be pleased to note that her body is more in proportion; her head doesn't seem as large in comparison to the rest of her. You'd see that her ankles and wrists have formed, and her fingers and toes are now visible too.
As her body begins to mature, her neck will start to develop and elongate. At this point, your baby's head still makes up more than half of her body size.
Small changes are taking place throughout baby-to-be's body, making her appear more and more like the newborn you'll be greeting in 30 or so weeks. She's getting more practice moving her arms and legs as they continue to develop muscle and bone. (Still, you won't feel her movements for a few more weeks—be patient!) The fingers and toes that first formed with webbing in between are now becoming more distinct and separate. She can wiggle her toes and fingers with ease. And tiny finger nails and toe nails are appearing.
Amniotic fluid not only surrounds your baby on the outside, she might swallow it too. But don't worry—ingesting amniotic fluid isn't harmful to your growing baby. In fact, the exchange of fluids helps her lungs develop.
An ultrasound taken now would probably show that the yolk sac is separate, and the umbilical cord from the placenta to your baby would be visible. Your baby's intestines are still part of the umbilical cord, but they're starting to move into his abdomen and will soon be covered by skin.
As for his organs, several more are starting to function. His thyroid gland—the master switch for controlling his body's own unique chemistry—is now operating. His pancreas is making digestive enzymes, and his gallbladder is secreting bile; these functions will be essential for eating and digesting his own food after birth.
Your baby's lung tissue is continuing to develop, and his bones are forming, even in his fingers and toes. Cells in the tiny hollows of his bones will soon start making blood cells, a function that until now has been the job of his liver and spleen. His face is starting to look more human; he may even have his first permanent tooth buds, and he will soon be able to open his mouth and move his tongue. It won't be long before he's sticking that adorable pink tongue out at you!
Amniotic fluid: The liquid that surrounds a baby in utero. At first, this liquid is mostly water. At 10 weeks, the amniotic fluid contains other nutrients that help the baby develop. Amniotic fluid also acts as a cushion to protect the developing baby from any external force on the mother's abdomen.
Images courtesy of the American Institute of Ultrasound in Medicine (AIUM.org)