Fetal development timeline

Fetal Development Timeline

By megan.palmer

  • Fertilized Egg

    Begins to exist when the sperm penetrates the egg within the first 12 hours prior to the pronuclei joining.
  • Hour 12

    Hour 12

    Fertilization
  • Hour 12

    Hour 12

    Pronuclei Join Together

  • Zygote Stage Begins

    Occurs when the two pronuclei join together within the first 12 hours.
  • Hours 30-36

    Hours 30-36

    First Round of Mitosis
  • Hour 40

    Hour 40

    Second Round of Mitosis
  • Hours 50-60

    Hours 50-60

    Third Round of Mitosis
  • Morula Formed

    Morula Formed

  • Embryo Stage Begins

    Occurs after the third cleavage when the morula forms.
  • Day 6

    Day 6

    64 Cell Embryo Called a Blastocyst
  • Hatching

    Hatching

  • Day 8-10

    Day 8-10

    Implantation
  • Day 8-10

    Day 8-10

    Ectopic Pregnancy Could Occur

  • Day 12

    hCG Begins to be Secreted
  • Day 12

    Day 12

    Disc with Streak on the Underside forms the Mesoderm
  • Day 14-22

    Day 14-22

    Neural Tube Forms

  • Day 15

    First Missed Period
  • Day 21

    Day 21

    Heart Begins to Beat, Arm and Leg Buds Appear, Yolk Sac Makes RBCs.
  • Day 34-36

    Day 34-36

    Face Plates Forming
  • Day 34-36

    Day 34-36

    Cleft Lip or Palate May Occur
  • Week 6

    Week 6

    Muscles Form, Bent Neck, Webbed Hands and Feet, Segmented Back
  • Week 7

    Week 7

    Fingers and Toes Separate, Eyes & Ears Formed
  • Day 50

    Day 50

    Genitalia Begins to Differentiate, Eyelids Fuse, Amnion Surrounds Fetus

  • Fetal Stage Begins

    Occurs when all the baby's organs have formed and now move into a period of further development and mass growth.
  • Week 9-11

    Week 9-11

    Chorionic Villi Sampling Could be Performed
  • Week 14-15

    Week 14-15

    Amniocentesis Could be Performed
  • Month 6-7

    Month 6-7

    Eyes Open, Fat Added Under Skin, Head out of Proportion to the Body