Repro Flashcards
How is male female differentiation determined in the gonads?
Males have SRY gene expressed in primordial germ cells
Triggers degeneration of the cortex and development of the medulla
Releases androgens which maintain mesonephric duct and mullarian inhibiting substance degrading the paramesonephric
Females lack SRY in no primordial germ cells
Cortex develops and medulla degrades
Lack of androgens results in degradation of mesonephric duct, lack of mullarian inhibiting substance results in persistence of paramesonephric duct.
Where do the gonads develop from? What type of embryonic tissues are involved?
The urogenital ridge (intermediate mesoderm) and primordial germ cells (from the yoke sac)
What is the embryonic origin of the female internal genitalia?
Paramesonephric ducts fuse, and the (uterine) septum between them breaks down forming the uterus, cervix and upper vagina. The urogenital sinus (external) begins to cavitate forming the sinovaginal bulb then the lower vagina.
What are the parts of the indifferent genetalia? What do they form in males and females?
Genital tubercle - glans penis / clitoris
Genital folds - shaft, spongy urethra / labia minora, urethra, vagina
Genital swellings - scrotum / labia majora
How do the testis anchored to the abdomen? How do they descend?
Urogenital mesentery becomes caudal genital ligament attaching to posterior abdo
Gubernaculum descends from caudal testis to inguinal region.
Testis starts to descend down route of gubernaculum
Gubernaculum extends to scrotum
Outpouching of peritoneum follows anteriorly (processus vaginalis)
Why does the ovary stop descending?
Mechanical obstruction by mullarian duct
What forms the ligaments of the ovary?
Cranial genital ligament - suspensory lig. of ovary
Caudal genital ligament - ovarian lig. and round lig. of uterus
Parietal lateral plate mesoderm - broad ligament of uterus
Describe female gamete formation
Primordial germ cells
Replicate to 7million then die to 2 million
Oogonia
Enter meiosis then arrest at prophase 1
Primary oocyte
Surrounded by flat follicular cells
Primordial follicle
BIRTH
Most primordial follicles die leaving 40000
PUBERTY
1/12 20 primordial follicles start to mature
Follicular cells thicken and become cuboidal with multiple layers (granulosa). Secrete zona pellucidia. Connective tissue shell (theca)
Pre antral follicle
Fluid collects in granulosa
Antral follicle
Theca differentiates into theca interna and theca externa. Antrum expands
Mature (graffian) follicle.
Meiosis progresses to prophase 2
Primary oocyte to secondary oocyte and polar body
Ovulation
What are the stages of the menstrual cycle with rough times?
Follicular / proliferative - 0 to 12 days (some variability)
Ovulation - 12 to 14 days
Luteal / secretory - 14 to 28 days (fixed)
Describe spermatogenesis
Primordial germ cells on sex cords Spermatagonia BIRTH PUBERTY Sex cords hollow forming seminiferous tubules Spermatagonia cluster around the edge Some spermatagonia differentiate to a1 spermatagonia Undergo a fixed number of mitotic divisions all remaining joined by cytoplasm Spermatocytes Meiosis Spermatids Release into tubules Maturation Spermatozoa
What are hormones that influence levels of other hormones called?
Trophic
Describe the release of GnRH
Released into hypophesal portal circulation from hypothalamus median eminence. Pulsetile, slightly more frequent in the morning.
What characteristics are required of male sex hormone production to meet their reproductive needs?
Steady hormone concentration to ensure continuos sperm production. Slightly raised levels in early morning. Slightly raised levels when stimulated and reduced when stressed.
What do LH and FSH do in male gonads?
LH acts on laydig cells to release testosterone
FSH acts on sertoli cells to stimulate spermatogenesis and also releases inhibin
What do testosterone and inhibin do in males?
Testosterone has regulatory and determinative effects.
Regulatory includes maintenance of repro tract, behaviour, promoting spermatogenesis by acting on sertoli cells alongside FSH
Determinative effects include secondary sexual characteristics
Testosterone feedback negatively on GnRH and LH + FSH (reduces secretion of GnRH and sensitivity of Gonadotrophin to GnRH).
Inhibin feeds back negatively on FSH
Explain the hormone changes in the proliferative / follicular phase of mensturation and the effects on the oocyte.
Initially low oestrogen and inhibin therefore uninhibited GnRH secretion.
As GnRH secretion increases increased LH and FSH
FSH causes granulosa to develop and inhibin to be released
LH causes theca to release androgens which are converted to oestrogens by granulosa
As follicle grows oestrogen and inhibin increase. Oestrogen inhibits GnRH and reduces sensitivity of gonadotrophs.
LH falls a bit but FSH falls markedly preventing further oocytes from developing. Oestrogen continues to rise as the follicle grows.
What is the effect of rising oestrogen during the proliferative/follicular phase on the female?
Endometrial proliferation (stratum basalis producing a new stratum functionalis. Arterioles lengthen and penetrate the new stratum functionalis)
Myometrium grows and contracts more
Cervical mucus becomes thin and alkaline
Systemic changes in hair, skin, metabolism.
What happens during ovulation?
Oestrogen levels climb. Switches to +ve feedback at hypothalamus and pituitary increasing LH levels +++. LH surge. LH breaks down theca externa collagen causing rupture and ovulation. This leaves the reminents of the follicle, the corpus haemorrhagicum.
As follicle ruptures oestrogen levels decrease, back to -ve feedback, LH and FSH drop.
What occurs in the secretory/luteal phase?
Corpus haemorrhagicum to corpus luteum.
Corpus luteum secretes oestrogen, progesterone and relaxin
Oestrogen decreases GnRH amount per pulse, progesterone decreases number of GnRH pulses and prevents any positive feedback from oestrogen.
O+P cause thickening of endometrium, thick acidic cervical mucus, increased body temp, metabolic changes, mammary changes.
How long does the corpus luteum last if no hCG is detected? What does it become? What happens?
14 days - becomes corpus albicans.
Decrease o+p, decrease blood supply to placenta, menses. Cycle starts again.
What are the strands of connective tissue that support the breast called? What causes laxity?
Suspensory ligaments
Age, strain
What is the structure of the glandular tissue of the breast?
Alveoli into lobules into 20 lobes
Lobes to secondary tubules to mammary duct to lactoferrous sinus to lactoferrous duct to nipple.
What determines breast size?
Amount of subcutaneous fat
What is the lymphatic drainage of the breast?
Sub areolar lymphatic plexus
Most to the axillary (pectoral), some to supra clavicular or deep cervical. Some medially to the parasternal
What is the histology of the ovaries?
Cortex with germ cells
Medulla connective tissue, blood vessels and nerves
What are the areas of the Fallopian tubes? What are their histology?
General - mucosa, lamina propria, muscular externa and serosa.
Fimbria
Infundibulum
Ampulla - heavily folded, bilayered muscle, cilliated columnar
Isthmus - lightly folded, trilayered muscle, peg cells
Intramural
What are the layers of the uterus?
Compact and spongy stratum functionalis (endometrium) Stratum basalis (endometrium) Myometrium
What is the histology of the cervix?
Near the internal os - simple columnar
Near the external os - non keratanized stratified squamous
Junction is the squamatocolumnar junction.
What makes pre puberty and puberty distinct?
The repro system could work pre puberty but GnRH secretion is low (thus low LH and low sex steroids).
What triggers puberty?
Unknown - something from the brain
Maybe body weight - 47kg trigger for menarch (though actually proportion of genetically expected weight) possibly signalled by leptins.
Maybe light levels producing melatonin from pineal gland
Why might age of puberty decreased over generations?
Increased body weight
Increased exposure to light (artificial)
Define precocious puberty
Onset of puberty prior to 8 years old
What can cause precocious puberty?
Idiopathic
Pineal tumour
Meningitis
Ectopic GnRH tumours
Why would cause early onset secondary sexual characteristics but not fertility?
Ectopic sex steroid producing tumour
What is the order of development in females during puberty?
Thelarche - breast development
Andrenarche - pubic hair growth
Growth spurt
Menarche - menstruation
What is the age of onset of puberty in females?
What is the age of onset of menarche?
8-13
11-15
What hormones are responsible for female pubertal development?
Thelarche is oestrogen
Anderarche is testosterone
Growth is both
Menarche is LH and FSH
When does puberty begin in males?
9-14
What order do events occur in male puberty?
Testicular growth
Penis size
Adrearche
Growth spurt
Why do males grow taller than females?
Testosterone is a bigger driver of growth than oestrogen
Longer period of growth (though later onset)
Why does early puberty cause short stature?
Less normal growth before growth spurt and growth plates seal after a set time during puberty.
Why do females experience menarche?
Follicles running out therefore reduced oestrogen.
What are the stages and typical ages of menopause, what happens to hormone levels and fertility?
Pre-menopause (from 40 years) causing erratic ovulation and mensturation with reduced but not absent fertility. Corpus luteum doesn’t always form. Less oestrogen and inhibin lead to raised LH and FSH.
Menopause (around 50 years), no follicles left to develop, oestrogen and inhibin levels fall thus LH and FSH very high.
What are the symptoms of menopause?
Hot flushes Regression of uterine tissue Loss of breast tissue Loss of vaginal rugae Vaginal dryness
Increased risk of osteoporosis
Increased risk of CVD
What are the sub classifications and definitions of amenorrhea?
Primary
Absence of menses aged 14 with no secondary sexual characteristics
Or
Absence of menses aged 16 with secondary sexual characteristics
Secondary
Menses in the past but none for 3 months if used to be regular or 9 months if used to be irregular.
What are the 2 most common cause of secondary amenorrhoea?
Preggers
Menopause
What are pituitary/hypothalamic causes of amenorrhoea?
Primary - congenital failure to produce gonadotrophins
Secondary - weight loss/anorexia nervosa, stress, exercise, pituitary necrosis, hyperprolactinaemia, haemochromatosis
What are gonadal causes of amenorrhoea?
Primary - chromosomal abnormalities (eg turners), receptor abnormalities (eg congenital adrenal hyperplasia)
Secondary - pregnancy, menopause, POS, drug induced
What are outflow tract causes of amenorrhoea?
Primary - mullarian agenesis, vaginal atresia (causes cryptomenorrhoea)
Secondary - endometrial adhesions (often follows dilation and cutterage abortions).
What sort of things should you ask in a history about amenorrhoea?
? Preggers Sexual Hx Contraception Weight change Medications Fhx (esp. Menopause)
What should you examine in an amenorrhoea consultation?
BMI Hair distribution Thyroid Visual field Breast discharge (hyperprolactinaemia) Abdominal masses
What is the term for heavy periods?
Menorrhagia
What is the term for painful periods
Dysmenorrhoea
What is the term for infrequent periods?
Oligomenorrhoea
What are the layers surrounding the testis? What do they originate from?
Tunica vaginalis (procerous vaginalis) Spermatic fascia (transversalis fascia) Cremastic fascia and muscle (internal oblique muscle) External spermatic fascia (external oblique muscle)
How does the histology of the male reproductive tract change?
Rete testis - simple cuboidal
Ductus efferentes - cilliated simple columnar, simple columnar
Epididymis - psudostratified columnar with steriocilia
Vas deferans - psudostratified columnar with sparse steriocilia
There is increasing amounts of muscle as you move distally.
How is testicular temperature regulated?
Held outside of the body
Pampiniform plexus of veins helps cool arterial blood
Dartos muscle contracts the scrotum when cold
What is the lymphatic drainage of the testis? What is the clinical significance of this?
The para aortic nodes
They can’t be palpated
What is the arterial supply and venous drainage of the testis?
Arterial supply - testicular arteries from the abdominal aorta
Venous drainage - testicular veins - right to IVC left to left renal vein
What is contained in the spermatic cord?
Testicular artery and vein Lymphatics Genital branch of genitofemoral nerve Obliterated procerous vaginalis Vas deferans
Where are the dartos and cremaster muscle located?
Dartos in the scrotum outside of the spermatic fascia
Cremaster in the middle layer of spermatic fascia
What is the innervation of the scrotum?
Anterior - genital branch of genitofemoral
Posterior - pudendal nerve from sacral plexus
Where in the prostate is bph more likely to effect? What about cancer?
Bph central zone
Ca peripheral zone
What are the cavities of the penis?
One corpus sponginosum
Two corpora cavenosa
What muscles are associated with the penis?
Bulbospongiosus
Ischiocavernosus
What lines make up the pelvic brim?
Lina terminalis made of arcuate line, pectineal line and pubic crest.
The sacral promonatory.
What are the three conjugates of the pelvis?
Anatomical - superior to sacral prominotory
Obstetric - middle to sacral prominotory (smallest)
Diagonal - inferior to sacral prominotory (easy to measure)
What is the entrance and exit to the true pelvis?
Entrance is the pelvic brim
Exit is pubic arch - ischial tuberosity - sacrotuberous ligament - coccyx
Differentiate a gynaecology from an android pelvis
Gynacoid has a greater than 90 degree pubic arch More oval brim Less prominent ischial spines A wider greater sciatic notch (more posterior coccyx)
What is the arterial supply to the ovaries uterus and vagina?
The ovarian artery (ovary and anastomoses with uterine)
The uterine artery (uterus and anastamoses with both)
The internal pudendal artery (vagina)
What glands are found in the vaginal vestibule?
Bartholin / vestibular
Explain the uterine position
The uterus is usually antiverted (rotated forward with respect to the vagina axis) and antiflexed (rotated forward with respect to the axis of the cervix).
With a full bladder the uterus can become retroverted.
What are the pouches around the uterus?
Uterovesicular pouch - bladder to uterus
Retro uterine pouch - uterus to rectum
What are the pouches within the vagina at the point of connection to the cervix?
What is the medical application?
The anterior and posterior fornices
Posterior fornix used for withdrawing fluid from rectouterine pouch by culdocentesis
What is the lymphatic drainage of the uterus?
Fundus to aortic nodes
Body to external iliac
Cervix to external and internal iliac as well as sacral
What muscles make up the pelvic floor?
Levator ani - puborectalis, pubococcygeus, iliococcygeus, coccygeus
Piriformis
What is the nervous innervation to the pelvic floor?
Pudendal nerve (s2 3 and 4)
What is the perineum?
What are. It’s boundaries?
How can it be divided?
A fibromuscular sheet which closes the outlet to the true pelvis
Pubic symphysis to ischiopubic ramus to ischial tuberosity to sacrotuberous ligament to coccyx.
Divided into anterior and posterior triangles
What muscles anchor to the perineal body?
Bulbospongiosus
External anal sphincter
Transverse perineal
What passes through the pelvic floor?
The urogenital hiatus comprising of the:
Urethra
Vagina
Anus
What prevents vaginal prolapse?
The uterosacral ligament acting as a sling
The arcus tendinous compressing the vagina
The perineal body anchoring the vagina in the perineum
What are the functions of the pelvic floor?
Support the pelvic organs preventing prolapse
Contributes to urinary continence (increased bladder pressure mimicked by increased sphincter pressure)
Contributes to bowel continence (puborectalis causes flexure in rectum)
Contributes to childbirth and truncal stability
What can cause pelvic floor weakness?
Childbirth stretches the ligaments, muscles and nerves (pudendal) Age Menopause Obesity Chronic cough Connective tissue disease
Why is incidence of STIs rising?
Greater awareness so greater presentation with symptoms or for screening
Greater promiscuity and risky sexual behaviour
Decline in fear of HIV
Better diagnostics
Why may many STIs go unrecognised?
Asymptomatic Denial Lack of awareness of symptoms Embarrassment Presentation to GP not GUM (statistical only)
Who is most at risk of STIs?
Young Poor Uneducated Ethnic minorities Early sex Multiple partners at once Unprotected sex Many partners lack of confidence
As well as direct treatment what else should be carried out on discovering an sti?
Contact tracing
Anti clamydia treatment
Advice on abstinence until cured
Advice on future safe sex
What causes genital warts?
What treatment?
What other disease is associated with it?
Human papillomavirus
Nothing/cryotherapy/surgery
Associated with cervical cancer (HPV 16 and 18)
What causes herpes?
How does it present?
What treatment?
Herpes Simplex Virus (usually type 2 though can be 1)
Painful multiple blisters that ulcerate. First episode associated with fever.
Treat with acyclovir if severe, salt water baths to keep area clean
What causes chlamydia, how does it present, what is the treatment?
Chlamydia trachomatis
Gram -ve coccus or rod
Urethritis, Epididymitis, prostitis, cervicitis, salpingitis
Can cause conjunctivitis in neonates (trachoma)
Treat with doxycycline
What causes gonorrhoea, how does it present, what is a common complication, how do you treat?
Neisseria gonorrhoeae
A gram -ve intracellular diplococcus
Causes urethritis, proctitis, prostatitis, Epididymitis and is often asymptomatic in females
Can spread to skin and joints
Treatment is with IM ceftriaxone and oral ciprofloxacin
What is trichomoiasis, what are symptoms, what tests, what treatment?
Trichomonas vaginalis Protazoa Burning/itching to vagina with offensive smelling discharge Perform culture Tx with metronidazole
What is syphilis, what are the stages of disease, what is Dx and Tx?
Treponema pallidum a spirochete
Painless ulcer to fever rash and lymphadonopathy to chronic granulomas to cvs and CNS pathology
Dx with dark field microscopy or serology
Tx with penicillin
What causes candidiasis, what are risk factors, what are symptoms, what is treatment?
Candidia albicans
Risk include dm, abx, ocp, pregnancy, steroids
Symptoms include white discharge and itch
Dx with smear
Txt with azoles, nystatin,
What is bacterial vaginosis, symptoms, Dx, Tx
Non sexually. Transmitted Gardnerella sp. mycoplasma, anaerobes Offensive fishy discharge Dx with wiff test Tx with metranidazole.
What is PID?
An ascending infection causing endometriosis, salpingitis, parametritis, oophritis.