ANATOMY OF THE FEMALE PELVIS

Question 1

describe the embryology of forming the female gonads?

Answer 1

we lose the mesonephros. at around the 10th week, we see the 2 paramesonephric ducts sticking together at the back of the bladder to form the genital canal which is connected to the urogenital canal by the sinuvaginal bulb.
at 20 weeks the paramesonephric ducts have fused together and created a large chamber which will be the precursor to the body of the uterus. the sinuvaginal bulb extends an forms the majority of the vagina. the wall between the vagina and urogenital sinus is called the hymen.

Question 2

desrcibe the peritoneal pouches?

Answer 2

the recto-uterine pouch is between the uterus and rectum whilst the vesico-uterine pouch is between the bladder and uterus.

Question 3

why is it important clinically to know about the peritoneal pouches?

Answer 3

if any fluid collects in the peritoneal region, then it will pool in the pouches which can cause infections and perforations.

Question 4

what is the broad ligament?

Answer 4

the 2 layer of peritoneum that loop over the top of the uterine tube stick together to form a mesentery

Question 5

describe the anatomy of the uterine tubes?

Answer 5

the ovaries are enclosed at one end by the infundibulum which has fimbriae around the edge. The ligament of ovary sticks to the edge of the body of the uterus and then continues on as the round ligament of uterus which runs through the inguinal canal and is embedded in the tissue of the labia majora.

Question 6

describe the histology of the body of the uterus?

Answer 6

the inner most layer is the endometrium, then the myometrium and then the peritoneum.

Question 7

describe the 2 sublayers of the endometrium?

Answer 7

stratum functional and stratum basale

Question 8

why is the uterus draped in peritoneum?

Answer 8

to separate and protect it from the abdominal cavity

Question 9

describe how the endometrium changes through the menstrual cycle?

Answer 9

during the menstrual phase, we see the shedding of the endometrium and then after around 5 days, there is the proliferation of the endometrium. in the secretory phase, uterine glands start to proliferate

Question 10

what is within the endometrium?

Answer 10

blood vessels and uterine glands

Question 11

what is the function of uterine glands?

Answer 11

transport and secrete substances essential for survival and development of the embryo

Question 12

what is the cervix?

Answer 12

the neck of the uterus

Question 13

what is the opening called between the cervical canal and the vagina?

Answer 13

the external Os

Question 14

what is the gully around the external Os called?

Answer 14

a fornix

Question 15

what is the histology of the cervical canal?

Answer 15

simple columnar epithelium

Question 16

what is the histology of the vagina and ectocervix?

Answer 16

stratified squamous epithelium (needs to be stronger to be able to resist friction)

Question 17

describe the arterial blood supply of the female pelvis?

Answer 17

the ovarian artery off the aorta for the gonads
the uterine, vaginal and internal pudendal arteries off the internal iliac atery
these arteries all form anastomoses ipsilaterally and contralaterally

Question 18

what are the bulbs of vestibule?

Answer 18

two bulbs of erectile tissue on top of the perineal membrane that start close to the inferior side of the body of the clitoris.

Question 19

what are the greater vestibular glands? where do we find them?

Answer 19

Bartholin’s glands- secrete fluid to lubricate the vagina

located on either side of the vaginal opening

Question 20

what are the less vestibular glands? where do we find them?

Answer 20

Skene’s glands- secrete a substance to lubricate the vagina
found either side of the urethra
n.b. these are homologous to the prostate glands

Question 21

which muscles are attached to the perineal body?

Answer 21

bulbospongiosus
superficial transverse perineal muscle
levator ani muscles (iliococcygeus, pubococcygeus, puborectalis)

Question 22

what hormone is responsible for external genitalia development?

Answer 22

oestrogen

Question 23

describe external genitalia embryology?

Answer 23

The genital tubercle only elongates slightly to form the clitoris.
The urethral folds and genital swellings do not fuse, but instead form the labia minora and labia majora respectively.
The urogenital groove therefore remains open, forming the vestibule into which the urethra and vagina open.

Question 24

what is the gubernaculum?

Answer 24

where the gonads are tethered to the labia

Question 25

what does the gubernaculum become in females?

Answer 25

the ovarian ligament and round ligament of the uterus

Question 26

what innervates the female perineum?

Answer 26

the pudendal nerve

dorsal nevre of the clitoris

Question 27

what is the blood supply of the female perineum?

Answer 27

the internal pudendal artery

branches are deep and dorsal arteries of the clitoris, artery of the vestibular bulb and posterior labial artery

Question 28

where does the deep dorsal vein of the clitoris drain into?

Answer 28

the vesicle plexus