-
Start
Fertilization -
Fertilized Egg
Begins when the sperm meets the egg -
Day 1, hour 12
pronuclei join together -
Zygote Stage Begins
Occurs when the pronuclei join together -
Day 2 hour 6
First Round of Mitosis -
Day 2, Hour 16
Second Round of Mitosis -
Day 3, Hour 2
Third Round of Mitosis -
Morula formed
-
Embryo Stage Begins
Occurs after the 3rd round of mitosis -
Day 6
64 Cell Embryo called a Blastocyst -
Day 10
Ectopic Pregnancy could occur -
Hatching
-
Day 12
Disk with streak on the underside forms mesoderm -
Day 12
Implantation -
Day 12
hCG begins to be secreted -
Day 14-22
Neural Tube Forms -
Day 15
First Missed Period -
Day 21
Heart begins to beat, arms & leg buds appear, yolk sac makes RBCs -
Day 34, 35, 36
Face Plates Form -
Week 6
Muscles form, bent neck, webbed hands and feet, segmented back -
Week 6
Cleft lip or palate may occur -
Week 7
Fingers & Toes separate, Eyes & Ears Formed -
Fetal Stage Begins
Occurs when all organs are formed -
Day 50
Genitalia begins to differentiate, Eyelids fuse, Amnion surrounds fetus -
Week 9-11
Chorionic Villi Sampling Could be Performed -
Week 14-15
Amniocentesis could be performed -
Month 6
Eyes open, fat added under skin, head out of proportion to the body
