Your little one is up to between 1 ?- 2 ? inches in length, measuring from crown to rump. By the end of this week, your baby will weigh about 8 grams and his or her ?tail? will have completely vanished. Your baby is looking more and more like a human baby all the time! During this time, your baby?s most vital body systems are already in place, completely developed and beginning to function, but they will continue to grow. These internal organ systems include: the circulatory system, nervous system, reproductive system and digestive system.
Your baby?s heart is continuing it?s job of pumping blood to all of your baby?s many internal organs, including the umbilical cord. This cord is the tube that contains arteries and veins, particularly two major arteries and one major vein, which connects your baby to the placenta. The vein inside the cord carries nutrient-rich blood and oxygen to your baby, while the two arteries within the cord return blood from your baby to the placenta.
The arms and legs are growing longer, but are still quite thin. Your baby?s joints are fully formed and he or she is very active at this stage. Your baby has been flexing his or her arms and legs, but you still can?t feel these movements, because your baby is still too small for you to notice. Your baby?s fingers and toes have been webbed up until now. They are newly-separated and clearly defined. These fingers and toes are actually growing little nails already! Can you believe that your baby has the ability to grab onto an object if something were placed in his or her tiny hand now? Absolutely amazing! Fingerprints have even appeared on your baby?s tiny fingers by now.
External genitalia is present and beginning to show male and female characteristics this week, although your baby?s gender was determined the very moment conception occurred; nine weeks ago. It will still be several weeks before it?s possible to tell by ultrasound if your baby is a boy or a girl, but ultrasound images aren?t fool-proof, therefore they cannot guarantee the gender.