Placental and Hormonal Physiology of Pregnancy Flashcards
At how many days does the … attach to the lining of the uterus
… = blastocyst
5-8 days
Match:
Inner cells develop into
Outer cells develop into
Embryo
Placenta
Outer = placenta Inner = embryo
What is the name of the type of cells that penetrate the endometrial lining?
Trophoblastic cells
What is the decidua?
Modified part of endometrium that forms in preparation of implantation
By what day should implantation have taken place?
Day 12
How does the implanted embryo start to get maternal blood?
How does this maternal blood then mix with foetal blood?
Trophoblasts imbed into the decidua and lose their nuclei to form multinucleate syncytiotrophoblasts
These invade the decidua and create lacuna (spaces) which then fill with maternal blood
Developing embryo sends projections into the synctiotrophoblast forming villi -> transfer of nutrients can then occur (NO direct contact between blood)
What is the placenta made up of and when is it fully functional?
Decidua and trophoblast tissue
18-20wks
What hormone is responsible for telling the corpus lutem to keep secreting progesterone?
Why is progesterone important in early stages?
HCG
Provides nutrition for early foetus
The placenta play the role of the foetal lungs describe blood flow from umbilical arteries/vein to the placenta and what happens when it gets there?
Arteries - carry mixed blood
Vein - carry oxygenated blood
One vein with arteries wrapped around
When it reaches the placenta it forms end capillary networks surrounded by intravillus space.
Intravillus space is full of maternal blood which allows exchange of gases and nutrients
PLEASE rewatch video to remind self
What are the 2 important factors about foetal Hb?
What effect does this have on oxygen dissociation graph?
Increased ability to carry O2 in high CO2 (where normally would want to give off O2) - stronger affinity for O2
Higher Hb concentration in foetal blood
Left shift
What is the baby’s main source of energy?
Glucose
Why is it so important to monitor what drugs are given during pregnancy?
Can transfer and cross the placental barrier
Match the following pregnancy hormones to their function:
hCG
hPL
Progesterone
Oestrogen
- Decreases insulin sensitivity in mother - more glucose for baby
- Maintains corpus luteum
- Breast development
- Growth hormone-like effects - protein tissue formation
- enlargement of uterus
- relaxation of ligaments
- development of decidual cells
- preparation for lactation
- decreases uterus contractibility
hCG
- maintains corpus luteum
hPL
- breast development
- growth hormone-like effects - protein tissue formation
- decrease insulin sensitivity for mother
Progesterone
- development of decidual cells
- decreases uterus contractibility
- preparation for lactation
Oestrogen
- enlargement of uterus
- breast development
- relaxation of ligaments
hCG can be used to help diagnose type of pregnancy. What kind of pregnancy is associated with hCG levels that:
- double
- fall
- static or slow rising
At what stage does it level out and start to decline slightly?
Double - normal viable
Fall - failing
Static or slow rising - ectopic
Week 8-10
Where is HCG produced?
Placenta produces it
