Female reproductive anatomy/histology Flashcards
What is the vulva?
- External female genitalia
- Responsible for sensation during sexual intercourse, directing flow of urine and protecting internal reproductive tract from infection
What structures are contained within the vulva?
- Mons pubis
- Labia majora
- Labia minora
- Vestibule
- Bartholin’s glands
- Clitoris
Vascular supply of the vulva
Arteries: internal and external pudendal
Veins: pudendal veins
Lymph drainage: superficial inguinal lymph nodes
Innervation of the vulva
Sensation:
- Anterior: ilioinguinal and genitofemoral nerves
- Posterior: pudendal nerve and posterior cutaneous nerve of thigh
PNS:
- Only found in clitoris and the vestibule
- Cavernous nerves
Anatomical relations of the vagina
Anterior: bladder and urethra
Posterior: rectouterine pouch, rectum and anal canal
Lateral: ureters and levator ani m.
What are the fornix of the vagina and where are they located?
- Vagina has 2 fornix - anterior and posterior
- They are located at the proximal end of the vaginal canal, near the opening of the cervix
- Posterior fornix is a natural reservoir for sperm
What are the four layers of the vaginal wall?
- Stratified squamous epithelium
- Elastic lamina propria
- Fibromuscular layer of smooth muscle (inner is circular, outer is longitudinal)
- Adventitia
Vascular supply to the vagina
Arterial:
- Uterine and vaginal arteries
- Both from the internal iliac
Veins:
- Vaginal venous plexus -> uterine veins -> internal iliac vein
What are the three zones which lymph drains to from the vagina?
- Superior aspect drains to external iliac nodes
- Middle aspect drains to internal iliac nodes
- Inferior aspect drains to superficial inguinal nodes
What is the innervation of the vagina?
Autonomics:
- Uterovaginal plexus - from the inferior hypogastric plexus
Somatic:
- Only in inferior 1/3 of vagina
- From deep perineal branch pudendal n.
Define the structure of the cervix
Ectocervix:
- The part of the cervix that projects into vaginal canal
- Non-keratinised stratified squamous epithelium
- Separated from endocervical canal by external os
Endocervix:
- Proximal part of cervix
- Mucous secreting, simple columnar epithelium
- Separated from uterus by internal os
Neurovasculature of the cervix
Arterial supply: uterine artery
Venous drainage: uterine vein
Lymphatic drainage: iliac, sacral, aortic and inguinal lymph nodes
Innervation: uterovaginal plexus
What are the three parts of the uterus?
Fundus:
- Top of uterus, above fallopian tube entry point
Body:
- Site of implantation of blastocyst
Cervix:
- Lower part of uterus, connects to vagina
NOTE: has same neurovasculature as cervix
What is the anatomical position of the uterus?
Anterior to the rectum, posterosuperior to the bladder
- Anteverted: rotated forward with respect to vagina
- Anteflexed: flexed anteriorly with respect to the cervix
What are the 3 layers of the uterus?
Outer serosa/adventitia:
- Serosa: connective tissue + visceral peritoneum
- Adventitia: only connective tissue
Myometrium:
- Thick layer of smooth muscle (~2cm)
- Grows significantly during pregnancy due to hyperplasia and hypertrophy
Endometrium:
- Inner mucosal layer
- Epithelium: simple columnar epithelium with ciliated and secretory cells
- Lamina propria: simple tubular glands in connective tissue
What are the two parts of the endometrium?
Functionalis:
- Part that is lost during menstruation and replaced during each cycle
- 2 layers: zona compacta, spongiosum layer (deep)
Basalis:
- Retained after menstruation to them proliferate into new endometrium
- Base of glands are source of new cells which regenerate the endometrium
What are the two phases of the endometrium?
Follicular/Proliferative phase:
- Oestrogen causes mitotic activity in glands and stroma
- Increase in endometrial thickness
Luteal/Secretory phase:
- Progesterone causes restriction of mitotic activity
- Endometrial glands secrete glycogen rich vacuoles to cause stromal cell enlargement and oedema, and spiral artery development
What are the features of the proliferative phase?
- Long, straight tubular glands
- Pseudostratified columnar epithelium
- Stroma rich in spiral arteries
- Lots of mitosis, lack of secretions
What are the features of the secretory phase?
- Saw-tooth and coiled glands
- Lack of mitosis
- Heavy secretions
What is the function of the fallopian tubes?
- Fertilisation of the egg occurs in the ampullary region (it is possible for ectopic implantation of the egg to occur in the fallopian tubes)
- They are not directly connected to the ovaries
- Hormones cause fimbriae to swell with blood during ovulation. The cilia then sweep the ovum into the fallopian tube
What are the four regions of the fallopian tubes?
- Isthmus (connected to the uterus)
- Ampulla
- Infundibulum
- Fimbriae (at end of ovaries
What are the layers of the fallopian tubes?
Mucosa:
- Simple columnar epithelium
- Ciliated + secretory cells
Lamina propria:
- Loose connective tissue
Muscularis:
- Inner circular + outer longitudinal layers of smooth muscle
What are the ovaries?
- They develop in the abdomen, descend through inguinal canal
- Paired organs, attached to posterior surface of broad ligament by mesovarium
What is the structure of the ovary?
Surface: simple cuboidal epithelium
Outer cortex: connective tissue stroma + ovarian follicles
Inner medulla: lots of connective tissue + rich vascular supply
Vascular supply to the ovaries
Arteries: ovarian arteries
Veins: ovarian veins
- Left ovarian vein -> left renal vein
- Right ovarian vein -> IVC
Lymph drainage: para-aortic lymph nodes
Innervation of the ovaries
ANS from ovarian and uterine plexuses (both originate from inferior hypogastric plexuses)
What are the two parts to an ovary?
Cortex:
- Outer layer
- Consists of follicles at varying stages of development
- Remainder of cortex is connective tissue with fibroblasts
Medulla:
- Inner layer
- Loose connective tissue stroma with rich vascular bed
- Large follicles may extend into here
What are the different stages of follicle development? (7)
- Primordial follicle
- Primary follicle
- Secondary follicle
- Early antral follicle
- Antral follicle
- Graffian follicle
- Corpus luteum + corpus albicans
What is a primordial follicle?
- Primary oocyte surrounded by simple squamous epithelium of stromal/pre-granulosa cells
- 30 micrometres in diameter
- Found at cell periphery
What is a primary follicle?
- Simple cuboidal epithelium of granulosa cells
- Roughly 75 micrometres in diameter
What is a secondary follicle?
- Zona pellucida forms between follicles + granulosa cells
- Granulosa becomes stratified cuboidal epithelium
What is an early antral follicle?
- Start of antrum formation
- Synthesis and secretion of oestrogen start
What is an antral follicle?
- Displays complete antrum formation
What is a Graffian follicle?
- This is the development of the dominant follicle
- Corona radiata is present
- Restriction of blood flow to the oocyte can cause follicle to rupture and release oocyte
What is a corpus luteum?
- The ruptured follicle will be retained in the ovary as a corpus luteum after ovulation - it secretes progesterone and oestrogen
- Develops a rich blood supply
What is a corpus albicans?
- If fertilisation of the egg does not occur, the corpus luteum degenerates into corpus albicans
- It is fibrous white tissue that is slowly absorbed into the ovary and leaves a visible white “scar”
