Fetal Development of the 1st Trimester

Congratulations! You can officially call yourselves parents now. You will now, until birth, have family and friends bombarding you with a million questions, like: how does it look now?, who do you think it will resemble more?, Can I feel it kick?, Can I rub your belly?, and the most infamous, Is it boy or a girl?

Fetal development typically follows the same course every time, it'll be easy to apprehend the advancement of the embryo. The first trimester is when most of the activity takes place, so I provided a calendar that consists of  the first twelve weeks (3 months) of fetal development.

Month 1 of Pregnancy:

During the first month of development a membranous sac surrounds itself around the fertilized egg, providing cushion for the growing embryo throughout the pregnancy. The placenta is also developed in this stage in order for the embryo to receive nutrients from the mother. A distinction of the face, eyes, mouth, jaws, and throat are being taken into shape. Meanwhile, blood cells are beginning to form and circulation will begin.

Month 2 of pregnancy:

Your baby's facial features continue to mature.Each ear begins as a little fold of skin at the side of the head. Tiny buds that eventually grow into arms and legs are forming. Fingers, toes, and eyes are also forming in the second month of pregnancy.The neural tube (brain, spinal cord, and other neural tissue of the central nervous system) is well arranged. The digestive tract and sensory organs begin to develop. Bone starts to replace cartilage, and the embryo begins to move, although  you will not feel it yet.

Month 3 of Pregnancy:

By end the of final month of your first trimester your baby is fully formed. Your baby has arms, hands, fingers, feet, and toes and can open and close its fists and mouth. Fingernails and toenails are beginning to develop and the external ears are formed. The beginnings of teeth are forming. Your baby's reproductive organs also develop, but the baby's gender is difficult to distinguish on ultrasound. The circulatory and urinary systems are working and the liver produces bile. At the end of the third month, your baby is about 7.6 -10 cm (3-4 inches) long and weighs about 28g

 (1 ounce).

References:

 WebMD. Ed. Michael W. Smith, Brunilda Nazario, and Hansa Bhargava. WebMD, 8 July 2012. Web. 11 May 2013. <http://www.webmd.com/baby/1to3-months>.