Prenatal Development Timeline
By: Kaityn Hendrix
*The moment fertilization takes place, the baby's genes and sex are set in place.
*hCG- A pregnancy hormone detected by pregnancy tests 3-4 weeks from the first day of your last period.
Cleavage, Blastula Stage, and Gastrulation
*The morula is created about 96 hours after conception, and is known as a collection of about 30 cells.
- This is the beginning of the embryonic period
- This is the time where the embryo consists of the two layers; the epiblast and hypoblast
- The amniotic sac, amniotic fluid, and yolk sac are all present
- At this time, the embryo is made up of three layers- Ectoderm, mesoderm, and endoderm. These will be what form all of the babies organs and tissues later on.
- The neural tube, nerves, and backbone are starting to develop in the top layer.
- The embryo's skeleton begins to develop
- The baby has its first heartbeat and the heart is beating about 100 to 160 times a minute
- The nose, mouth, and ears are beginning to take shape and the lungs and intestines are beginning to develop.
- The umbilical cord has blood vessels to carry oxygen and nutrients back and forth to the baby now.
- Both hemispheres of the brain are growing.
- Hands and feet are starting to show up on the arms and legs
- The hands and feet are starting to develop webbed fingers and toes.
- The baby is beginning to move around, but he is still too small and the movements too fine to be able to feel them
- The embryonic tail is now gone
- The internal sex organs are there but are not distinguishable
- This marks the beginning of the fetal period where the babies tissues and organs will rapidly grow and mature.
- The vital organs of the baby are functioning
- 11: The baby can now hiccup
- 12: The baby's reflexes have developed, so he can now open and close his fingers and curl his toes
- 13: The baby now has fingerprints
- 14: The baby can squint, frown, and suck his thumb
- You may be able to tell the sex of the baby with the use of an ultrasound!!
- The skeleton of the baby changes from cartilage to bone (ossification)
- Myelin (a protective covering) is beginning to form around the baby's nerves