Imagine you are carrying a teeny-weeny person inside you! That’s right – your little baby already has inceptions of limbs and internal organs. The little arms that will energetically wave in a few months upon seeing mommy are only fragile ossicles now. And the legs – they will appear later.
This is hardly the fourth week of your pregnancy, and the baby already has a heart and blood circulation! Furthermore, all major organs are also developed. His/her head is clearly defined, as well as his/her tapered tail. The central nervous system continues being formed within three bulbs on the nervous tube. The cerebrum will originate namely from these bulbs. However, the spinal cord is already at its place. It is quite long and reaches far to the tail. Its fast development can be easily noticed in contrast to that of the abdomen. This is the exact reason why your midget looks like a comma. Organs of sense are developed, such as incepts of internal year, eyes, future jaws. The little papilla that will grow into a little tongue with which the baby will playfully pull faces at you is also there. The slight extended area is the place of the future stomach, and against it we can see the inceptions of liver, gall and pancreas. The little baby also has initial formations of trachea and windpipe, as well as thyroid gland and hypophysis. The primary cells that will form the sex cells also shift to the place where they will be further developed. All these special adjuncts and future organs are comprised within 5mm.