Fetal Development Flashcards
Amniotic Fluid
- 98% water
- Slightly alkaline
- Contains fetal urine, nutrients, hormones, antibodies, skin cells, & lanugo
The average volume of amniotic fluid at birth
800-1000mL
(Poly)hydramnios
> 2000mL of amniotic fluid
Oligohydramnios
<300mL of amniotic fluid
Functions of amniotic fluid
- Maintains even temperature
- Permits embryo to float and develop symmetrically
- Aids in the development of lungs and GI
- Cushions against blows to the abdomen
Placenta
- Temporary organ
- Forms around week 3 and grows through week 20
Maternal Side of Placenta
- “Raw beefy” appearance
- “Dirty Duncan”
Fetal Sid of Placenta
- Shiny appearance
- “Shiny Schultze”
- Umbilical cord attached in center
Placenta Funtions
- Gas exchange between mother and fetus
- Nourishment and Excretion
- Hormone Production
- Barrier to nicotine, drugs, alcohol, viruses can cross
How does the placenta perform gas exchange
2 arteries carry deoxygenated blood to mother and 1 vein carries oxygenated blood to fetus
How does the placenta aid in nourishment and excretion
Delivers nutrients and clears fetus’s metabolic waste products
Placenta Hormones
- Influences growth and maintains pregnancy
- HCG, Estrogen, Progesterone, HPL, Relaxin
Wharton’s Jelly
Substance surrounding umbilical cord that keeps the vessels separate to keep the cord from kinking
Pre-embryonic Stage
Begins with fertilization through implantation
What does ectoderm form?
Skin & nervous system