Ch. 6 Coneption Flashcards
Define conception
Union of single egg and sperm marks beginning of pregnancy
Where does fertilization take place
ampulla of uterine tube
When does implantation occur
6-10days after conception
What is the purpose of the chronic villi
Vascular process that obtain oxygen and nutrients from maternal bloodstream and dispose of carbon dioxide
How long does pregnancy last
9months, 40wk, 280days
How long does the embryo stage last
Day 15-8wk after conception
When are all organ systems and external structures present
End of 8wk
When does the fetus start urinating into amniotic fluid
Week 11
What are the function of amniotic fluid
Maintain body temperature, source of oral fluid , repository for waste, fluid and electrolyte balance, cushion, barrier for infection and allows lung development
Define oligohydramnios
Having less than 300ml of amniotic fluid; associated w/renal abnormalities
Define hydramnios
Having more than 2l of amniotic fluid; associated with gastrointestinal malformation
When does the primitive heart begin to neat and circulate blood through embryo
End of 3rd week
Why is progesterone needed to maintain pregnancy
It maintains the endometrium, decreases contractility of the uterus, stimulates maternal metabolism, development of aveoli
How does estrogen aid in maintaining pregnancy
Stimulates uterine growth and uteroplacental blood flow, causes proliferation of the breast tissue, stimulates myometrial contractility
What are the metabolic functions of the placenta
Respiration, nutrition, excretion, storage
In what position is optimum circulation achieved for the pregnant women
Lying at rest on her side
How long does the fetus stage last
From 9wk (fetus is recognizable)
Define viability
Capability of the fetus to survive outside the uterus
When is the heart completely developed
By end of embryo stage
What is the average FHR
110-160bpm
Define hematopoietic
Formation of blood, occurs in yolk sac beginning 3rd week
When does the respiratory tract begin formation
Week 4-week 17
When is sufficient surfactant present in developed aveoli to provide infants with a good chance of survival
32weeks
What is the most critical alveolar surfactant required for postnatal lung expression
Lecithin; detectable at 21weeks
What ratio is used to determine fetal lung maturity
L/S ratio reaches 2:1, occurs at 35weeks
When is the gastrointestinal system mature
36wk
Why do newborns get an administration of vitamin K
Coagulation factors cannot be synthesized in fetal liver because they lack vitamin K synthesis in the sterile gut
When can the fetus make respiratory movement, move all extremities, change positions
11-12wk
When do fetuses respond to sound
24week
When is the fetus distinguishable (male/female)
By week 9
When can a women expect to feel the baby move
16-20wk