Female reproductive system Flashcards
Development
gonads in both sexes begin to develop during the 5th week as masses of
intermediate mesoderm called gonadal ridges, which form dorsal AW
- paramesonephric duct = future female ducts
Internal female organ development
Female embryos – sexual differentiation begins in Week 8.
- Cortical portion of immature ovaries forms ovarian follicles.
- Paramesonephric duct becomes uterus, uterine tubes, superior part of vagina
- Mesonephric ducts degenerate
External organ development
both females & males: small projection, genital tubercle, on external perineal surface.
- urogenital sinus (future urethra and bladder) lies deep to tubercle.
- The urethral groove, serving as external opening of urogenital sinus, runs between genital tubercle and anus, laterally flanked by urethral folds & labioscrotal swellings
External female organ development
genital tubercle -> clitoris, unfused urethral folds -> labia minora, unfused labioscrotal swellings -> labia majora; urethral groove -> vestibule
Female reproductive system
external: mons pubis, labia majora (enclosing pudendal cleft), labia minora (enclosing vestibule), clitoris, bulbs of vestibule, greater/lesser vestibular glands
internal: ovaries, UT, uterus, vagina
Mons pubis
rounded fatty eminence overlying pubic symphysis
Labia majora vs. minora
- Labia majora - prominent outer folds of skin, w/subcutaneous fat and termination of round ligament of uterus, external aspect covered w/pigmented skin w/sebaceous glands, smooth IA
- Labia minora - inner folds of fat-free skin,
have a core of spongy connective tissue
containing erectile tissue & small blood vessels, IA contains many sensory endings
Clit and vestibule
- Clitoris – erectile organ, where labia minora meet A, consists of a root and a body, composed of 2 crura, 2 corpora cavernosa, and glans of clit covered by a prepuce.
- Vestibule – space surrounded by labia minora, contains the openings of urethra, vagina, and ducts of the greater/lesser VG
Vestibule bulbs and VG
- Bulbs of vestibule – paired masses of elongated ET, along the sides of vaginal orifice deep to bulbospongiosus, homologous w/bulb of penis and CS
- VG - greater vestibular (Bartholin) glands on each side of the vestibule, P to vaginal orifice, glands open into vestibule, secrete mucus during sexual arousal, lesser VG open between the urethral and vaginal orifices and secrete mucus
Ischiocavernosus & Bulbospongiosus
- Ischiocavernosus - maintains erection of
clit by compressing outflow veins - Bulbospongiosus – “sphincter” of vagina,
assists in erection of clit and bulb of vestibule, compresses greater vestibular
gland
Superficial transverse perineal muscle
supports and fixes the perineal body and pelvic floor to support viscera
Vagina
mostly sub peritoneal muscular membranous tube, extends from cervix of uterus -> vestibule of vagina, serves as
canal for menstrual fluid, forms the I part of birth canal, plays role in reproduction
Vaginal structure
communicates S to w/cervical canal, I to vestibule, typically collapsed – A & P walls in contact, except S -> held apart by cervix
- Vaginal fornix – recess around the protruding cervix, has A, P, & L parts
Vasculature of vagina
Arteries - supplying S part of vagina derive from the uterine arteries
- middle & I parts derive from vaginal and internal pudendal arteries
Veins - form plexuses along sides of
vagina and within vaginal mucosa, drain into internal iliac veins via uterine veins
Ovaries
Almond-shaped organs found near attachment of broad ligament to L pelvic walls.
- Suspended by peritoneal folds: mesovarium and suspensory ligament of
ovary.
- Attached to uterus by ligament of ovary
Ovarian structure
ovaries are connected to body wall via
ligaments/mesenteries, but not directly attached to uterine tubes, an egg released by ovary must be ‘swept’ into UT
Uterus
hollow thick-walled muscular organ receives, retains, and nourishes fertilized egg.
- Adult uterus – usually anteverted (tipped
AS relative to axis of the vagina), position changes due to degree of fullness of bladder and rectum
- nongravid uterus usually lies in LP, w/its body lying on UB and cervix between bladder and rectum
Uterine structure
- Body – includes rounded fundus, constricted isthmus, and uterine horns; freely movable.
- Cervix – cylindrical, narrow I part of uterus
Uterine Wall
- Perimetrium – outer serous coat, consists
of peritoneum and CT - Myometrium – middle muscular coat, distends during pregnancy, main branches of blood vessels and nerves located here
- Endometrium – inner mucous layer, adheres firmly to myometrium, involved in menstrual cycle, if conception occurs, blastocyst implanted here, otherwise, inner surface of coat shed during menstruation
Uterine (Fallopian) tubes
Extend L from uterine horns, open into peritoneal cavity near the ovaries.
- Lie in mesosalpinx in free edge of broad ligament, position is variable.
- The uterine tubes have no contact w/ovaries, ovulated oocyte casted into
peritoneal cavity.
- 4 parts: infundibulum (funnel-shaped
distal end opens into peritoneal cavity, fimbriae), ampulla (widest/longest part), isthmus (enters uterine horn), and uterine portion (short intramural segment)
Uterine and Ovarian ligaments
Broad ligament of uterus – a 2x layer of peritoneum, extends from sides of uterus to L walls and floor of pelvis.
- helps keep uterus centered in pelvis and contains ovaries, UT, and related structures, & vasculature that serves them
- Suspensory ligament of the ovary – a L extension of broad ligament over ovarian vessels
Ligaments (3)
- Mesovarium - portion of broad ligament suspending ovary
-Mesosalpinx - suspends UT - Mesometrium - major part of broad ligament of uterus
Breast
Mammary glands: modified sweat glands found in superficial BW
- Suspensory ligaments of breasts- thickenings of fascia, anchor breast to skin, separate glandular and fat lobules.
- Lobules drain into lactiferous ducts, open on nipple
Space between breast and BW
- superficial to pectoralis major, minor, + serratus A muscles
- Retromammary space: a potential space b/n breast and underlying deep pectoral fascia – allows some degree of movement of breast
