Fetal Development Timeline

By 2018harreba

  • Week 4

    Week 4
    The inner group of cells will become the embryo. The outer group will become the cells that nourish and protect it. On contact, it will burrow into the uterine wall for nourishment. This process is called implantation. The placenta, which will nourish your baby throughout the pregnancy, also begins to form. The embryo is about 1/4" long. http://www.baby2see.com/development/week4.html
    http://www.baby2see.com/development/week7.html

  • Week 7

    Week 7
    The embryo is around 13 mm (1/2 inch) in length. The baby's eyes and inner ears are starting to develop. It is about now that your baby's major organs (heart, lungs liver, spleen, and kidneys) are beginning to develop. Your baby's digestive system is becoming more refined as the stomach and intestines develop. http://www.baby2see.com/development/week7.html http://www.baby2see.com/development/week8.html

  • Week 8

    Week 8
    The embryo is measures about 18 mm (3/4 inch) in length. The arms and legs continue to develope. The pituitary gland is also forming and the embryo is beginning to grow muscle fibers. The baby's facial features are visible, including a mouth and tongue. The eyes have a retina and lens. The major muscle system is developed, and the baby starts to practice moving. http://www.baby2see.com/development/week8.html

  • Week 10

    Week 10
    The unborn baby is now called a fetus. Though the fetus is constantly moving, you will not be able to actually feel fetal movement for several more weeks. All of the organs, muscles, and nerves are in place and beginning to function. As the hands and feet develop fingers and toes, they have lost their paddle like look. The touch pads on the fingers form and already have fingerprints. http://www.baby2see.com/development/week10.html
    http://www.baby2see.com/development/week7.html

  • Week 13

    Week 13
    The fetus is now 3 inches long and weighs about an ounce. The baby's unique fingerprints are already in place. The muscles lengthen and become organized. You can't feel it yet, but your baby can move in a jerky fashion, flexing the arms and kicking the legs. http://www.baby2see.com/development/week13.html

  • Week 17

    Week 17
    At week 17 of fetal development, the fetus weight is just over 5 ounces. The baby is about 5 inches (14cm) and would be about 9 inches (23cm) head to toe, if it could stretch out. The umbilical cord is growing thicker and stronger. Fat stores begin to develop under your baby's skin this week. The fat will provide energy and help keep your baby warm after birth. http://www.baby2see.com/development/week17.html

  • Week 23

    Week 23
    The baby is over 11 inches tall, weighs about a pound. The eyebrows are visible. Bones located in the middle ear harden. Your baby does a regular 'workout' inside your womb. He or she turns from side to side and head over heels. Thanks to a fully developed inner ear, which controls balance, your baby may have a sense of whether he or she is upside-down or right side up in the womb. http://www.baby2see.com/development/week23.html

  • Week 27

    Week 27
    During this week, the fetus weighs almost 2 pounds now and is about 14.5 inches long. Your baby now appears much like he or she will look like at birth. Baby now has eyebrows and eyelashes and hair is growing everyday. The muscle tone is improving and his or her body is getting plumper. The retina at the back of your baby's eyes is beginning to develop and they can now open their eyes. http://www.baby2see.com/development/week27.html

  • Week 33

    Week 33
    The baby inside you is now about 4.4 pounds and around 17.5 inches in length. The baby is using it's lungs to practice breathing by inhaling amniotic fluid. Your baby is drinking about a pint of amniotic fluid a day now and urinating the same amount. The early baby fuzz, lanugo, is disappearing now and being replaced by actual hair. The nails of your baby are now long enough to reach to the tip of the fingers. http://www.baby2see.com/development/week33.html

  • Week 40

    Week 40
    He or she is getting ready for birth and is settling into the fetal position with its head down against the birth canal, its legs tucked up to its chest, and its knees against its nose. The bones of baby's head are soft and flexible to ease the process of delivery through the birth canal. Your baby is now about 20 inches (51 centimeters) long and weighs approximately 6 to 9 pounds. http://www.baby2see.com/development/week40.html