Stages of Pregnancy
Watch a slideshow with the stages of development month by month:
In just four weeks, the heart, brain, and spinal cord begin to form. Major organs like the stomach and intestines are already forming, as well as the eyes and ears.
The first trimester is a period of tremendous growth. Within 6 weeks, the unborn child’s heart is beating and brain activity can be recorded.
In 8 weeks, all the major organs have begun to develop. The unborn child’s facial features become recognizable, including the nose, lips, and tongue. After 10 weeks, the unborn child has enough muscle control to make its hand into a fist.
By the close of the first trimester, all of the organs and body parts have been formed, including the nerve fibers that transmit pain signals to the brain.
At the beginning of the second trimester, major organs such as the liver and the pancreas begin to function. The unborn child begins to make movements that can be felt by its mother. Detailed features begin to form, including fingernails, taste-buds, and eyelashes. After 20 weeks, some experts have concluded that the unborn child is able to feel pain.
At the end of the second semester, the unborn child becomes more animated. It can hear outside noises, hiccup, squint, smile, and frown. Its unique footprints and fingerprints have formed. The lungs have developed to the point it maybe possible for a prematurely born baby to survive, although they may incur serious disabilities.
A newborn is considered full-term once it has developed for 38 weeks. The weeks leading up to that point are the final stages of growth. After 26 weeks, the unborn child exercises its muscles by kicking and stretching. The bones are fully developed and the brainwaves resemble those of a fully developed baby.
Between 34 and 36 weeks, the eyes begin to open when the unborn baby is awake and close when he or she sleeps. It weighs between 5 to 6 pounds and measures between 16 and 19 inches long. If the baby should be born prematurely, the chances of survival are excellent, although the newborn might need special care.