Uterus, Uterine Tubes & Cervix Flashcards
What is the uterus lining?
Lined by the endometrium (thin lining inside)
The muscular layer is the myometrium
The perimetrium is the outermost layer
How are the ovaries attached?
Ovaries attached by a ligament close to the fimbrial end of the uterine tube
Where us the most common place for fertilisation to occur?
Ampulla of the uterine tube is where fertilisation occurs
When is the egg normally released for fertilisation?
Egg released from uterine tube around the first ⅚ days and fertilised in ampulla
What is the role of the cervix?
Cervix acts as the mucosal plug but allows sperm to pass through
What is the effect of maternal steroids on the uterus?
Maternal steroids increase size of new-born uterus.
How does uterus grow in newborns?
Grows with height during infancy.
Myometrium dependent on estradiol.
Corpus of uterus undergoes greater increase in size than cervix.
Why is a newborns uterus bigger than a 4 y/o
A newborns uterus is bigger in size compared to a 4y/o due to high estradiol exposure in utero causing larger myometrium
What is the myometrium?
Outer muscular myometrium grows gradually throughout childhood.
How does the myometrium change during puberty?
Increases rapidly in size and configuration during puberty.
How is the myometrium altered during menstrual cycle?
Changes in size through the cycle. Capable of vast expansion during pregnancy.
What are the 3 muscular layers of the myometrium?
3 muscular layers of myometrium:
- Inner layer circular fibres
- Middle layer figure of 8 or spiral fibres
- Outer layer longitudinal fibres
Explain how the endometrium differs in size due to age
Very thin in childhood. Begins to thicken at puberty.
What causes changes in endometrial size?
Dependent on steroids. Responds cyclically to hormone changes.
How can the endometrium be viewed clinically?
Can be seen and measured on an ultrasound scan. Good ‘bioassay’ of estradiol level…7-16mm
What happens to the endometrium during the menstrual cycle?
Changes in glandular and epithelial cells through cycle. At menstruation most of the endometrium is lost
Describe the fate of the endometrium after menstruation
After menstruation - stromal matrix with small columnar cells with glandular extensions 2-3mm thick
glands are simple and straight.
What stimulates the proliferative phase (follicular phase)?
Proliferative phase in endometrium is stimulated by estradiol from the dominant follicle. (in ovary this is called follicular phase)