Siggy is my sister's baby (in utero) and here is a cool update of what he is doing in there...
Your baby's weight has doubled in two weeks and now weighs about 3.5 ounces! The crown-to-rump length of your growing baby is 4.4 to 4.8 inches. If you spread your hand out opened wide, you can see about how big your baby is.
Your uterus is moving up and is now approximately 1.5 to 2 inches below your navel. You are showing more now and there is a noticeable swelling in your abdomen. At this point in your pregnancy, a 5 to 10 pound weight gain is normal. Other people can probably feel the difference in your lower abdomen if they were to rub your tummy. To be the most comfortable, you should be wearing maternity clothes or clothing that is too large for you. You may have felt your baby move already. However, you might not feel it move every day at this point. As your pregnancy progresses, movements become stronger and more frequent. Feeling your baby move can help reassure you that your baby is doing well. You might also notice that your gums or nose bleed occasionally. This is from the increased blood volume that puts pressure on small blood vessels and capillaries.
Huge changes continue to take place within your developing baby. This week fat begins to form and will continue to do so until he is born. Fat is important to the body's heat production and metabolism. Right now, at 17 weeks, water makes up about 3 ounces and fat 0.018 ounces of your baby's body. In a baby at term, fat makes up about 5.25 pounds of the total average weight of 7.7 pounds. The placenta is continuing to grow at an amazing rate. The placenta will continue to develop in tandem with the fetus and it will weigh more than a pound at birth! By this week, the placenta is large and well established with a network of blood vessels that exchange nutrients and waste.
The eyes are facing more forward. The ears are now close to their final position.
Your baby is more flexible with ability to move head, mouth, lips, arms, wrists, hands, legs, feet, and toes.
Fingerprints are forming now.