FEMALE REPRODUCTIVE ORGANS Flashcards
(41 cards)
what is the uterus?
= a thick-walled, pear-shaped, hollow muscular organ where the embryo and fetus develop
where does the nongravid uterus lie?
in the lesser pelvis with its body lying on the urinary bladder and its cervix between the urinary bladder and the rectum. Immediately posterosuperior to the bladder and anterior to the rectum.
it is anteverted with respect to the vagina and anteflexed with respect to the cervix.
name the 3 parts of the uterus and where they are
- fundus: farthest from the opening. top of the uterus, above the entry point of the uterine tubes
- body: largest part of the uterus. usual site of implantation of the blastocyst
- cervix: neck of the uterus, projects lower end into the vagina. cervical canal passes through (ectocervix (external os) and endocervical canal (internal os))
name the 3 tissue layers the fundus and body are composed of
peritoneum, myometrium, endometrium
what are the peritoneum, myometrium and the endometrium?
- peritoneum: a double layered membrane, continuous with the abdominal peritoneum
- myometrium: thick smooth muscle layer. cells of this layer undergo hypertrophy and hyperplasia during pregnancy in preparation to expel the fetus at birth
- endometrium: inner mucous membrane lining the uterus, further divided into the deep stratum basalis and the superficial stratum functionalis. where blastocyst is implanted.
what is the difference between the deep stratum basalis and the superficial stratum functionalis?
- deep stratum basalis = changes little throughout the menstrual cycle and is not shed at menstruation
- superficial stratum functionalis = proliferates in response to oestrogens, and becomes secretory in response to progesterone. it is shed during menstruation and regulates from cells in the stratum basalis layer
broad ligament
a double layer of peritoneum, attaching the sides of the uterus to the pelvis. acts as mesentry for the uterus and contributes to maintaining its position.
offers little support but the neurovascular supply to the ovaries, uterine tubes and uterus pass between the folds of the peritoneum.
further divides into mesometrium , mesovarium and mesospalinx
round ligament
maintains anteverted position of the uterus. a remnant of the gubernaculum, extending from the uterine horns to the labia majora via the inguinal canal
ovarian ligament
joins the ovaries to the uterus
cardinal ligament
located at the base of the broad ligament. it extends from the cervix to the lateral pelvic walls. contains the uterine artery and vein, also provides support to the uterus
uterosacral ligament
extends from the cervix to the sacrum — provides support
suspensory ligament
extends outwards from the ovary to the lateral abdominal wall. contains ovarian vessels and nerves
vascular supply of the uterus
- uterine artery
- uterine vein
- lymphatic drainage via iliac, sacral, aortic and inguinal lymph nodes
innervation of the uterus
sympathetic = sacral splanchnic nerves parasympathetic = pelvic splanchnic nerves (S2-S4)
function and shape of the uterine tubes
- conduct the oocyte
- provide the usual site of implantation
- lie in the mesosalpinx
- divided into 4 parts: fimbriae, infundibulum, ampulla, isthmus
describe the 4 parts of the uterine tubes
- fimbriae = finger-like projections which capture the ovum from the surface of the ovary
- infundibulum = funnel-shaped opening near the ovary to which the fimbriae are attached
ampulla = widest section of the uterine tubes, where fertilisation usually occurs - isthmus = narrow section of the uterine tubes connecting the ampulla to the uterine cavity
vascular supply and lymphatics of the uterine tubes
- uterine and ovarian arteries
- uterine and ovarian veins
- lumbar lymph nodes (aortic, sacral, iliac)
innervation of the uterine tubes
- sympathetic: lumbar splanchnic nerves (T12-L2)
- parasympathetic: pelvic splanchnic (S2-S4) and vagus nerves
what are the 3 layers of the uterine tubes?
- mucosa = highly folded, simple columnar epithelium with a thin lamina propria (supportive connective tissue), some cells ciliated and others secretory. Ensures the ovum is in contact with cilia so that it can be wafted towards the uterus
- muscularis = consists of 2 layers of smooth muscle, inner circular and outer longitudinal. purpose is peristalsis
- serosa = extension of the broad ligament
function, shape and location of the ovaries
= the female gonads
- almond shaped and sized
- where oocytes develop
- produce sex steroid hormones oestrogen and progesterone in response to LH and FSH
- each ovary is suspended by the mesovarium
- attached to the posterior surface of the broad ligament by the mesovarium
- each ovary lies within the peritoneal cavity against the lateral wall of the pelvis in a depression called the ovarian fossa.
3 layers of the ovaries
- surface = simple cuboidal epithelium (germinal epithelium). underlying this layer is a dense connective tissue capsule (tunica albuginea)
- cortex = compromised of a connective tissue stroma and numerous ovarian follicles. each follicle contains an oocyte, surrounded by a single layer of follicular cells
- medulla = formed by loose connective tissue and a rich neurovascular network, which enters the hilium of the ovary
vascular supply and lymphatic drainage of the ovaries
- ovarian artery
- ovarian veins. right to inferior vena cava, left to left renal vein
- via para aortic lymph nodes to lumbar trunks. ovarian lymphatic vessels (lateral aortic nodes)
innervation of the ovaries
- S: greater and lesser thoracic and sacral splanchnic nerves
- PS: pelvic splanchnic nerves (S2-S4)
vagina function, shape and location
- a distensible muscular tube which extends posterosuperiorly from the external vaginal orifice to the cervix
- roles = sexual intercourse, childbirth, menstruation
- anterior = fundus of bladder and urethra
- posterior = rectourine pouch, rectum and anal canal
- lateral = ureters and levator ani muscle and visceral pelvic fascia
