Baby is working hard this week. It will triple in size.
Its heart should start beating this week. Initial circulation starts off in the mesoderm, yolk sac and the linning of the placenta. By the middle of this week the aorta will have started to form in the baby’s heart.
Another major development this week is that the babys’ eyes will also begin to form, as well as the surface layer of skin.
The baby’s head and brain will also undergo some rapid development, the baby’s tongue and nasal pits will start to form, as well as “flippers” that will later become arms!!