10 Weeks

Though he's barley the size of a kumquat— a little over an inch or so long, crown to bottom — and weighs less than a quarter of an ounce, your baby has now completed the most critical portion of his development. This is the beginning of the so-called fetal period, a time when the tissues and organs in his body rapidly grow and mature.

He's swallowing fluid and kicking up a storm. Vital organs — including his kidneys, intestines, brain, and liver (now making red blood cells in place of the disappearing yolk sac) — are in place and starting to function, though they'll continue to develop throughout your pregnancy.

If you could take a peek inside your womb, you'd spot minute details, like tiny nails forming on fingers and toes (no more webbing) and peach-fuzz hair beginning to grow on tender skin.
(from: pregnancy.com)