Endocrinology of pregnancy Flashcards
In the male reproductive tract, which cells can produce oestrogen?
Leydig cells, germ cells
What is oestrogen required for in male bone development?
Bone strength and closure of growth plates in long bones
What 2 things are required for maturation of spermatozoon
Fructose and glycoproteins
What is the function of sugar and glycoproteins in sperm maturation?
- Energy provision
2. Surface coating
What induces GP and fructose release for sperm maturation, and where are they secreted into?
Androgens
Epidydmal fluid
Describe the control of tubular fluid reabsorption
Controlled by oestrogen, occurs in rete testis
By what process do sperm become mobile?
Capacitation
Where and how do sperm achieve fertilisation capacity?
Female reproductive tract:
Lose GP coat
Change in surface membrane
Tail movements begin
What is required for sperm capacitation?
Oestrogen
What name is given to the reaction when a sperm enters the ovum?
Acrosome reaction
Recall the events of the acrosome reaction
- Sperm binds to ZP3 on ovum surface
- Ca++ influx into sperm
- Hyaluronidase and proteolytic enzyme release 4. Sperm penetrates zona pellucida
Upon which hormone is the acrosome reaction dependent?
Progesterone
When is the 2nd polar body expelled from the ovum?
Upon fertilisation
What is triggered by release of the 2nd polar body?
Cortisol reaction
Recall the events of the cortisol reaction
Cortical granules release enzymes to degrade ZP
Sperm can no longer bind
How are additional sperm prevented from binding to the ovum once fertilisation has taken place?
Cortisol reaction degrades ZP
When does the ovum become diploid?
When it is fertilised
When is the fertilised egg first known as a “morula”
8 cells
Recall how the morula develops into the blastocyst
Has inner and outer cell masses:
Inner cell mass becomes embryo, outer cell mass destined to become chorion
Recall the 2 main factors involved in blastocyst implantation
Leukaemia-inhibitory factor
IL-11
Where is LIF produced and what is its role?
Produced in endometrial secretory glands
Stimulates adhesion of blastocyst to endometrial cells
What is decidualisation?
Process that changes underlying uterine stroma to facilitate implantation
Why is progesterone named as it is?
Pro-gesterone - promotes gestation: required for implantation
What is the main driver of decidualisation?
IL11
