How big is baby?

Your little embryo has now officially graduated to fetus-hood. Adding to the excitement, a Doppler ultrasound device might be able to pick up the beating heart. With basic physical structures in place and increasingly distinct facial features, baby is kind of starting to look like... well... a baby!
By now, your baby is being nourished through the placenta, a flat, spongy organ covered with wavy masses of capillary-filled tissue called chorionic villi. Nutrients pass through this tissue to the embryo, while wastes are carried away. The placenta and chorionic villi are made up of the same genetic material as the baby, and can offer important information about birth defects such as Down syndrome, Tay-Sachs disease, and cystic fibrosis.