The embryo is approximately 4mm in length, the size of a pinhead 
Amniotic fluid is building up
The placenta is developing, providing oxygen and nutrition to the embryo

The embryo has three layers. In the top layer, the neural tube will form which will develop into the nervous system. In the middle layer, the heart [...]

The embryo is approximately 6mm in length
Growth becomes rapid this week. The eyes, ears and an opening for the mouth begin to form. The heart is now pumping blood and most other organs are forming. Buds are forming which will later become the arms and legs.
You may start craving certain foods while the [...]

The embryo is now approximately 10mm in length
The lower jaw and vocal chords are beginning to form and teeth buds are now in place in the gums. The inner ear is also being created
You are not showing yet as your uterus is still smaller than a tennis ball. You may have lost a [...]