Scenario 21 Flashcards
What are the three layers of the uterus?
Serosa (parietal peritoneum), myometrium and endometrium
How is the cervix alkaline?
Constantly producing mucus
How does the vagina protect itself?
Rich in glycogen which attract bacteria that produce lactic acid
At what angle is the vagina at?
15 degrees backwards
How does the uterus lie?
Anteversed and antiflexed
What is the broad ligament?
A double fold of peritoneum draped over the uterus and its tubes
What are the suspensory ligaments?
Continuation fo the broad ligament onto the lateral pelvic walls
What is the round ligament?
distal part of the gubernaculum around the bladder
What are the cervical ligaments?
Pubocervical, transverse cervical and sacrocervical ligaments
Where is fertilisation most likely to happen?
Ampulla
Nerves to the female reproductive system
Symp T10-L1, Parasymp S2-4 Somatics Pudendal
Arterial supply to the area
Internal iliac arteries and ovarian arteries from AA at L2
When do we have our maximum number of primary oocytes?
23 weeks- 7 million
What does the primary oocyte number reduce to by birth?
2 million and 0.5-1 million by first menstrual cycle
What are the three ovarian cycle phases?
Follicular, ovulation and luteal
What are the three uterine cycle phases
Menstrual proliferative and secretory
What hormones are high in menstrual stage (first part of follicular)?
FSH and LH
FSH causes 20 antral follicles to be recruites with one becoming the Graafian follicle
Why does one of these follicle become dominant?
FSH causes the proliferation of granulosa cells in the follicles and LH receptors to be expressed on these cells by 10 days one follicle will be dominant and secrete oestrogen which causes a reduction in FSH levels causing atresia of the other non dominant follicles
What hormones are present in the proliferative phase (second part of follicular) day 6-14
FSH, Oestrogen (LH dropped)
What is the result of the production of oestrogen from the graafian follicle on the uterus?
Formation of a new endometrial layer and spiral arteries and cervix produces mucus to reduce the acidity of the vagina
What happens at ovulation?
LH levels rise and 36 hours after the graafian follicle ruptures and discharges an oocyte
What hormones are high in the secretory/ luteal phase?
Progesterone and oestrogen, FSH and LH dropping
How does the graafian follicle transform into the corpus luteum?
Remaining FSH and LH
What is the role of progesterone?
Makes the endometrium respond to implantation by causing the endometrial glands to secrete mucus and glycogen
Why do FSH and LH levels drop?
Suppressed by the progesterone and oestrogen from the corpus luteum
What happens to the CL as FSH and LH drop
Atrophy and death unless fertilisation occurs and hCG is produced which is structurally similar to LH meaning it can continue to make progesterone and oestrogen for 10-12 weeks until the placenta takes over
When does menstruation happen?
When the CL degenerates and oestrogen and progesterone levels drop- uterine gland are wide and spiral arteries start contracting
What does a small increase of oestrogen do?
decrease in FSH production
What does a large increase in oestrogen do?
increase LH production (late follicular phase)
How do we measure ovarian reserve?
1-antral follicle count (in early follicular phase)
Hormone levels- inhibitin B suppression of FSH secretion decreases so high FSH in early follicular phase, anti-mullerian hormone
What is the superficial fascia surrounding the external genetalia?
Colles
What is the smooth muscle surrounding the external genitalia?
Dartos muscle
What is the deep fascia over the penis?
Bucks
What is the contents of the spermatic cord?
3 arteries- testicular, cremasteric and ductus deferens
3 veins- pampiniform plexus, cremasteric, ductus deferens
3 nerves- autonomics (symp T10-11), genitofemoral (cremaster) and ilioinguinal
3 other things- ductus vas deferens, lymphatics and processus vaginalis remnant
3 layers- external fascia, cremasteric and internal spermatic fascia
How are the reproductive organs aroused?
Parasympathetics- pudendal nerve(S3)
How does ejaculation occur?
Phase 1- contraction of SM in wall of epididymis and vasa differentia of testes to peristaltically move spermatozoa to prostatic urethra where sympathetic stimulation causes sperm to be mixed with secretions from prostate and seminal vesicals (urethral sphincter closes)
Phase 2- contraction of skeletal muscle to pump semen down urethra
Where is the lymphatic drainage of the superficial perineum?
Superficial inguinal nodes
Where is the lymphatic drainage of the testes epididymis and the ductus deferens?
Para aortic nodes around L2
What is the arterial supply to the testes?
testicular arteries from AA at L2 through deep IR and into spermatic cord
Ductus deferens is supplied by the deferential artery
What is the venous drainage of the testes
Pampiniform plexus which forms a single testicular vein on the right to IVC at right and on the left joining left renal vein
What happens in the epididymis?
Sperm are concentrated
What is the role of the seminal fluid from the seminal vesicles?
Protein rich and high fructose to give the sperm energy. Prostaglandins to open the cervix and alkaline to neutralise the vagina
Where are the bulbourethral glands and what do they do?
In deep peroneal pouch and secrete mucus to lubricate the urethra (pierce at bulbous urethra)
What is the role of the prostate gland?
Contributes citric acid to seminal fluid and secretes proteolytic enzymes for phospholipid metabolism for maintenence of the sperm.
What is the lymphatic drainage of the prostate?
Para aortic nodes and cystera chyli cancer can also spread in venous plexus
Where in the ovaries are the follicles?
Outer cortex
What are the ovaries covered in?
Germinal epithelium and tunica albuginea
How are primary follicles formed before puberty?
Activated primordial follicles
How do these primary follicles become secondary follicles?
Flattened follicular cells become cuboidal and proliferate to give the zona glomerulosa and englarge and get surrounded in a glycoprotein coat (zona pellucida) the theca folliculi is formed and differentiates into theca interna and theca externa. Antrum forms in zona gomerulosa
What is the function of the theca interna?
Maked steroid hormones
What oocyte does the secondary follicle contain?
Primary oocyte
What happens when the monthly cycle starts?
FSH triggers 20 follicles to develop further, LH rises and stimulates theca interna to make oestrogen which suppresses FSH and only the Graafian follicle survives
What happens mid cycle when LH rises?
primary oocyte completes meiosis 1 and forms a secondary oocyte arrested at metaphase of meiosis 2
What happens at ovulation?
Follicle ruptures discharging secondary oocyte
What happens to the follicle after ovulation?
Collapses and granulosa cells form corpus luteum
What does the corpus luteum secrete?
Oestrogen and progesterone which suppress FSH and LH
Why does the corpus luteum degenerate?
No LH
What are the key features of the uterine tube?
Highly convoluted mucosa, inner circular and outer longitudinal muscle layers and simple columnar epithelium containing ciliated and secretory peg cells
What are the layers of the endometrium?
Stratum basilis which persists and stratum functionalis which is lost with menstruation
What is the epithelium transition at the cervix?
From the simple columnar of the uterus to the stratified squamous of the vagina
How many lobules are in the testes and how many seminiferous tubes to each?
400 and 1-4 tubes to each
Where do the seminiferous tubes drain to?
Rete testes and epididymis