THE OVARY

• 4x2 cm, attached to the posterior aspect of the broad ligament by a mesentery - the mesovarium
• Attached to the lateral pelvic wall by the suspensory ligament of the ovary (infundibulo-pelvic ligament)
• Attached to the upper part of the lateral uterine wall by the round ligament of the ovary (remnant of upper part of the gubenaculum)
• Position variable, but usually lies within ovarian fossa in lateral pelvic wall. The ovarian fossa is bounded superiorly by the external iliac vessels, inferiorly by the ureter and internal iliac vessels and its floor is crossed by the obturator nerve
• The ovary is surrounded by a thin fibrous capsule - the tunica albuginae
• Blood supply - ovarian artery - branch of abdominal aorta at L1
• Venous drainage - LEFT -left ovarian vein drains into left renal vein; RIGHT - right ovarian vein drains into inferior vena cava
• Lymphatics - para-aortic nodes
• Nerve - aortic plexus

FALLOPIAN TUBES

• ~10cm long, 4 parts
• Infundibulum - funnel-shaped lateral end, projects beyond the broad ligament with fimbriae at its free end
• Ampulla - widest and longest part, site of fertilisation
• Isthmus - narrowest part, just lateral to the uterus
• Intra-mural part - pierces uterine wall
• Three coats: serous, muscular, and mucous.
• The external or serous coat is peritoneal. The middle or muscular coat consists of an external longitudinal and an internal circular layer of smooth muscle fibers continuous with those of the uterus
• The mucosa is thrown into longitudinal folds, which in the ampulla are much more extensive than in the isthmus. Lined by ciliated columnar epithelium
• Blood - ovarian and uterine arteries
• Lymphatics - aortic and internal iliac nodes (follow arteries)
• Nerves - inferior hypogastric plexus

THE UTERUS

• 8cm long x 5cm wide x 2.5cm thick
• Covered by peritoneum except anteriorly below the reflection of the utero-vesical fold of peritoneum and laterally between the layers of the broad ligament
• Fundus - that part of the uterus above the entrance of the uterine tubes
• Cavity - triangular in coronal section, cleft in saggital section
• Anteverted uterus - long axis of uterine body at 90degrees to long axis of vagina
• Ante-flexed uterus - long axis of the body of the uterus bent forward at the level of the internal os
• Retroverted uterus - body and fundus bent backwards on the vagina to lie within the pouch of Douglas
• Anterior relations: utero-vesical pouch and superior surface of bladder
• Posterior: Pouch of Douglas, sigmoid colon and coils of ileum
• Laterally: uterine vessels, ureter
• Nerve - inferior hypogastric plexuses (Parasympathetic via the pelvic splanchnic nerves, sympathetic via the lumbar splanchnic nerves). Pain sensation is transmitted via the sympathetic nerves and the lumbar splanchnic nerves
• Lymphatics: Fundus - accompany ovarian artery to para-aortic nodes at the level of L1. Body of uterus and cervix - internal and external iliac nodes

LIGAMENTS OF THE UTERUS

• Transverse cervical ligament: fibro-muscular condensations of pelvic fascia pass from the cervix and upper end of the vagina to the lateral pelvic wall
• Utero-sacral ligament: cervix and upper end of vagina to the lower end of the sacrum - form two ridges on either side of the pouch of Douglas
• Pubo-cervical ligament: cervix to posterior surface of pubis
• Round ligament: Of the ovary - from medial margin of ovary to upper part of lateral wall of uterus. Of the uterus - from upper part of lateral uterine wall to deep inguinal ring
• The uterus is supported mainly by the tone of the pelvic floor muscles (levator ani) which are partly inserted onto the perineal body and condensations of pelvic fascia forming the transverse cervical, pubo-cervical and utero-sacral ligaments.

THE BROAD LIGAMENT

• Two layered fold of peritoneum extending from the lateral uterine wall to the lateral pelvic wall
• Has an upper free edge which contains the fallopian tube
• The layers of peritoneum separate inferiorly to cover the pelvic floor
• Has ovary attached to its posterior surface by the mesovarium
• Uterine artery crosses the ureter at the base (lower attached border)
• Round ligament of the uterus forms a ridge an the anterior surface
• Contains vestigial structures: epoophron and paroophron (remnant of the mesonephric system)
• Uterine and ovarian blood vessels and lymphatics run within it

THE CERVIX

• Lower, narrow portion of the uterus, connected to the uterine fundus by the uterine isthmus - upper limit is the internal os. Made up mainly of fibrous tissue with very little smooth muscle
• Protrudes through the upper anterior vaginal wall
• Approximately half its length is visible in the vagina (vaginal cervix), the rest being above the vagina (supra-vaginal cervix)
• The vaginal cervix ~3 cm long and 2.5 cm wide. Size and shape varies widely with age, hormonal state, and parity - bulkier and the external with a wider and more slit-like external os in multiparous women.
• Ectocervix - portion of the cervis beyond the external os - lined by stratified squamous non-keratinising epithelium.
• Endocervical canal - links external and internal os - lined by columnar epithelium
• The squamo-columnar junction - variable location - high up the endocervical canal before puberty and in the post-menopausal women. Site of origin of squamous cell carcinoma of the cervix
• The external os is bounded by two lips, an anterior and a posterior, of which the anterior is the shorter and thicker, although due to the slope of the cervix, it projects lower than the posterior. Both lips are in contact with the posterior vaginal wall
• The supravaginal cervix is separated in front from the bladder by fibrous tissue (parametrium), which extends also on to its sides and laterally between the layers of the broad ligaments. Not covered by peritoneum on the anterior aspect
• The uterine arteries reach the margins of the cervix within the parametrium
• The ureter runs downward and forward 2 cm lateral to the supravaginal cervix
• Posteriorly, the supravaginal cervix is covered by peritoneum, which extends on to the posterior vaginal wall, when it is reflected on to the rectum, forming the Pouch of Douglas which may contain coils of small intestine.
• The vaginal cervix projects free into the anterior wall of the vagina between the anterior and posterior fornices.
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Blood supply

• Uterine artery, branch of internal iliac
• Cervical and vaginal branches supply the cervix and upper vagina.
• The cervical branches of the uterine arteries descend on the lateral aspects of the cervix at 3 and 9 o'clock. Venous drainage parallels the arterial supply, eventually emptying into the hypogastric venous plexus.

Lymphatics

• Regional lymph nodes for the cervix include: paracervical, parametrial, presacral, sacral, external iliac, common iliac, hypogastric (obturator), internal iliac..

Support and innervation

• Mainly the cardinal (transverse cervical) and uterosacral ligaments.
• These attach to the lateral and posterior aspects of the supra-vaginal cervix and extend laterally and posteriorly bony pelvis.
• The uterosacral ligaments are the conduits of the main nerve supplying to the cervix, derived from the hypogastric plexus.
• Sensory, sympathetic, and parasympathetic fibers are present in the cervix
• Sensory fibres travel via the parasympathetic nerves (S2,3,4 - pelvic splanchnic nerves)
• Dilatation of the cervix using dilators may result in a vasovagal attack with reflex bradycardia
• The endocervix has a plentiful supply of sensory nerve endings, while the ectocervix is relatively lacking in these. Small cervical biopsies and cryotherapy can be performed in most patients without the use of anaesthesia

THE VAGINA

• ~8cm long, axis directed upwards and backwards from the vulva. Posterior wall longer than anterior wall
• Lined by stratified squamous epithelium which undergoes changes during the menstrual cycle. Does not secrete mucus
• Has anterior and posterior walls which are normally in apposition, and four fornices (anterior, posterior, left and right lateral)
• Upper half lies above the level of the pelvic floor

Relations

• Anterior: bladder, urethra
• Posterior: upper third - pouch of Douglas; middle third - ampulla of the rectum; lower third - perineal body
• Lateral: upper part - ureter, middle part - anterior fibres of levator ani; lower part - uro-genital diaphragm and the bulb of the vestibule

VAGINAL SUPPORT

The vagina is supported by

• Levator ani muscles, transverse cervical, pubo-cervical and utero-sacral ligaments in its upper part
• The uro-genital diaphragm in its middle part
• The perineal body in its lower part