Uterine cycle Flashcards
What are the 3 phases of the uterine cycle?
- Menses
- Proliferative phase
- Secretory phase
When does menses occur?
Day 0-5
When does the second phase of the uterine cycle occur?
Day 5-14 (proliferative phase)
When does the third phase of the uterine cycle occur?
Day 14-28 (Secretory phase)
Describe the first phase of the uterine cycle
In the absence of progesterone, the endometrium cannot be maintained so the functional layer of the endometrium is shed.
(Menses)
Describe the second phase of the uterine cycle
Increase in oestrogen. Causes growth of endometrium. Stroma proliferates to become thicker and more vascularised. New tubular glands form (that undergo increased mitotic activity) and stroma and blood vessels that grow from the stratum basalis. Because implantation requires easily penetrable, highly vascular tissue with lots of glycogen.
As tubular glands lengthen they convolute
Describe the third phase of the uterine cycle
- Prepares the endometrium for implantation.
- Secretions are produced to nourish the embryo
- Stroma is highly vascular and tubular glands are highly convoluted so they have a ‘saw-tooth’ appearance of glands which contains lots of thick glycogen and glycoprotein rich secretion.
- Lumen of the glands fill with secretory products
What are the 3 layers of the uterus superficial to deep?
- Endometrium
- Myometrium
- Perimetrium
Describe the endometrium
The inner layer of the uterus. Made up of glandular cells that make secretions
Describe the myometrium
The middle and thickest layer of the uterus wall. Made up of smooth muscle
Describe the perimetrium
The outer (deep) serous layer of the uterus
What are the 3 layers of the endometrium (superficial to deep)?
- Stratum compact
- Stratum spongiosum
- Stratum basalis
What layers of the endometrium make up the functional zone?
Stratum compact and spongiosum
Describe the functional zone of the endometrium
Undergoes monthly cycles of proliferation, secretion, necrosis and shedding
What is the function of the basal layer of the endometrium?
Doesn’t shed during menses and acts as a reservoir for the development of a new functional layer after shedding
Which hormone increases on days 0-14?
Oestrogen
What affect does oestrogen have on the cervix?
Causes cervical secretions to be more thin, water and full of electrolytes.
How does the cervical tissue change between days 0-14?
Becomes highly spinbarkeit (stretchable)
Which hormone increases on day 14-28?
Progesterone
What affect does progesterone have on the cervix?
Causes secretions to b e more thick and viscous
How does cervical tissue change between days 14-28?
Become low spinbarkeit (non-stretchable)
Which hormone increases speed of transport of gamete/early embryo?
Oestrogen
Which hormone decreases speed of transport of gamete/early embryo?
Progesterone
Define primary amenorrhoea
Failure to establish menstruation by 15yrs with normal secondary sexual characteristics (e.g. breast development) or 13 years with no secondary sexual characteristics
What does primary amenorrhoea with secondary sexual characteristics imply?
The problem is with the end sexual organ whereas if no sexual characteristics develop problem more likely to be hypothalamus or pituitary
Define secondary amenorrhoea
Cessation of menstruation for 3-6 months with previously normal and regular menses or for 6-12 months in women with previous oligomenorrhoea.
State 5 endocrine causes for primary amenorrhoea with normal sexual characteristics
Hypothyroidism, Hyperthyroidism, hyperprolactinaemia, Cushing’s syndrome, PCOS.
Could also be caused by pregnancy
Causes of amenorrhoea with NO sexual characteristics
Problems with hypothalamus or anterior pituitary.
Stress, exercise, weight loss
Chronic illness (diabetes, severe renal/cardiac disorders, Coeliac disease)
cancer and infection
