Female Pelvic Anatomy

Question 1

Ovaries

Answer 1

• Responsible for production of gametes and hormones (progesterone, oestrogen, inhibin and relaxin)

Question 2

Ovary Structure

Answer 2

• Cortex - surrounds medulla, made from a framework of connective tissue. Ovarian follicles covered by germinal epithelium.
• Tunica Albuginea, white capsule of dense connective tissue directly inside the germinal epithelium.
• Medulla - fibrous tissue, central in the ovary and contains blood and lymph vessels and nerves
• Ovarian follicles - Located in the cortex, consisting of oocytes in varying stages of development.
• Graafian Follicle - large and fluid filled and ready to rupture and release second oocyte.
• Corpus Luteum - remnant of mature follicle following ovulation. It produces progesterone, oestrogen, relaxin and inhibin. Degenerates into scar tissue.

Question 3

Ovarian Cycle

Answer 3

• Germ cells within the ovaries become oogonia.
• These divide to form germ cells and primary oocytes, surrounding themselves with follicles. Known as primordial follicles.
• Gonadotrophins, FSH and LH from pituitary gland stimulate primordial follicles and become primary follicles.
• Primary follicles consist of an oocyte surrounded by granulosa cells, located in cortex and secrete oestrogen as follicle grows.
• Develops into a secondary follicle, becomes a large fluid filled graafian follicle.
• The graafian follicle ruptures to free the secondary oocyte in the process of ovulation.
• This is called the ovum which is released into the uterine tubes and can go on to be fertilised during conception.
• Remnant follicle following ovulation is called the corpus luteum which releases progesterone, oestrogen, relaxin and inhibin.
• If there is fertilisation, the ovum attaches to the endometrium which is preparing for implantation.

Question 4

Ovarian Cycle 2

Answer 4

• Hormones continue to be secreted to aid embryonic development.
• If no fertilisation, there will be no implantation - hormone secretion changes and the endometrium is shed during menstruation.
• Corpus luteum degenerates into scar tissue.

Question 5

FSH

Answer 5

• Follicle stimulating hormone

- Produced by the anterior, initiates follicle growth

Question 6

Oestrogen

Answer 6

• Produced by follicle lining cells, stimulated follicles to mature

Question 7

LH

Answer 7

• Lutenising Hormone

- Produced by anterior pituitary, triggers ovulation

Question 8

Progesterone

Answer 8

• Produced by the corpus luteum

- Prepares endometrium for implantation

Question 9

HCG

Answer 9

• Human chorionic gonadotrophin
• Produced by the fertilised ovum
• Stimulates further oestrogen and progesterone production by corpus luteum to maintain pregnancy

Question 10

Blood Supply

Answer 10

• Arterial Supply - Ovarian arteries supply blood to ovaries from abdominal aorta
• Venous Drainage - In to a plexus of veins in the broad ligament, connects the side of the uterus to the lateral walls.
• Right ovarian Vein -> inf vena cava
• Left ovarian vein -> left renal vein

Question 11

Uterine Tubes/Fallopain Tubes

Answer 11

Divided into 4 areas:

• Infundibulum: funnel shaped opening close to the ovary but open to the pelvis
• Fimbriae: End of infundibulum - finger-like, ciliated projections, one of which attached to lateral end of the ovary. They capture the ovum from the surface of the ovary
• Ampulla: Widest, longest portion of the tubes. Fertilisation usually occurs here.
• Isthmus: Medial, short, narrow, thick walled section connecting the ampulla to the uterus.

Question 12

Ligaments

Answer 12

• Broad Ligaments: double fold of peritoneum, attach the uterus to the pelvic wall. They contain blood vessels and nerves as well as uterine tubes and ovaries.
• Round Ligaments: cord like ligaments attached to the uterus just below the uterine tube. They run laterally between folds of broad ligaments, lateral to the pelvic wall.
• Utero-Sacral ligaments: connect the uterus to the sacrum, originating from the posterior wall of the cervix and vagina. Run posteriorly either sie of the rectum to the sacrum.
• Cardinal Ligaments: from cervix and upper part of vagina to lateral pelvic walls

Question 13

The Uterus

Answer 13

• Thick walled muscular organ, capable for expansion.
• Connected distally to the vagina and laterally to the uterine tubes.
• Fundus - dome shaped portion, superior to the uterine tubes
• Body - central portion, tapers towards the inf end
• Cervix - inferior portion, opens into the vagina.
• Isthmus - constricted region between the body of the uterus and cervix.

Question 14

Body of the uterus

- Perimetrium

Answer 14

• simple squamous cells and areolar connective tissue
• Distributed differently on different surfaces of the uterus
• Anteriorly, it forms a pouch between the uterus and the bladder
• Posteriorly it forms a pouch between the uterus and the rectum
• Laterally - becomes a broad ligament, which at lateral ends attaches the uterus to the sides of the pelvis

Question 15

Body of the uterus

- Myometrium

Answer 15

• Middle layer of uterus
• 3 layers of smooth muscle
• thickest and the fundus and thinnest at the cervix

Question 16

Body of the uterus

- Endometrium

Answer 16

• Inner layer of the uterus
• Mucous membrane
• Richly supplied with blood - spiral arteries
• Divided functionally into two layers: -stratum functionalis - lines uterine cavity, is shed during menstruation
• Stratum basalis - never shed, provides new functionalis layer after menstruation

Question 17

Uterine Blood Supply

Answer 17

• Arterial supply from internal iliac vessels.
• Enter the uterus at the lower border of the broad ligament, near the isthmus.
• A good blood supply is necessary to support regrowth of the stratum functioalis after menstruation, implantation of the ovum and placenta development.

Question 18

The Vagina

Answer 18

• A muscular tube, 7.5cm anteriorly and 9cm posteriorly
• Extends from uterus to vulva
• Fornix - a recess surrounding the vagina at the attachment of the cervix
• Hymen - a think layer mucous membrane

Question 19

Structure of the Vagina

Answer 19

• 3 coats!
• Outer coat - loose areolar tissue, contains vessels and nerves
• Middle coat - smooth muscle, stretches to accommodate penis and allow child birth
• Inner coat of smooth muscle which consists of stratified squamous epithelium which secretes glycogen rich fluid that maintains a low pH in the vagina and provides protection from bacteria and causes a hostile environment for sperm.

Question 20

Vulva

Answer 20

• External female genitalia
• Mons Pubis - adipose tissue covered by skin and pubic hair, cushions symphysis pubis
• Labia Majora - 2 folds of skin covered in pubic hair, composed of adipose tissue, sebaceous and apocrine glands
• Labia Minora - 2 smaller folds of skin. No hair or fat - many sebaceous glands but few sudiferous
• Vestibule - between labia minora and clitoris
• Clitoris - nerve endings and erectile tissue
• Vestibular glands - bartholins glands - situated each side of vaginal opening, secrete mucus