Week seven! This information is from http://www.babycenter.com :)
How your baby's growing:
The big news this week: Hands and feet are emerging from developing arms and legs — although they look more like paddles at this point than the tiny, pudgy extremities you're daydreaming about holding and tickling. Technically, your baby is still considered an embryo and has something of a small tail, which is an extension of her tailbone. The tail will disappear within a few weeks, but that's the only thing getting smaller. Your baby has doubled in size since last week and now measures half an inch long, about the size of a blueberry.
If you could see inside your womb, you'd spot eyelid folds partially covering her peepers, which already have some color, as well as the tip of her nose and tiny veins beneath parchment-thin skin. Both hemispheres of your baby's brain are growing, and her liver is churning out red blood cells until her bone marrow forms and takes over this role. She also has an appendix and a pancreas, which will eventually produce the hormone insulin to aid in digestion. A loop in your baby's growing intestines is bulging into her umbilical cord, which now has distinct blood vessels to carry oxygen and nutrients to and from her tiny body.