Gross Anatomy & Histology of Female Reproductive System - 2 Uterus & vagina Dr. Sangeeta S Kotrannavar Assistant Professor, Dept. of Anatomy USM-KLE, IMP, Belagavi Learning Objectives • Explain the parts, location, relations, positions, supports, blood supply, lymphatic drainage and histological features of the uterus • Describe the peritoneal relations, fornices, lymphatic drainage, innervation and histological features of the vagina • Describe the applied anatomy of female reproductive system Female Reproductive System • Internal genital organs • Ovary • Uterine tubes • Uterus • Vagina • External genital organs • Receives Functions • Retains of uterus • Nourishes product of conception till maturity Uterus • It is a thick walled hollow muscular organ • Site - In the lesser pelvis, between urinary bladder (lies infront) and rectum (behind). • Communicates with the uterine tubes at its upper end, and below with the vagina Size & shape • Size • Length--7.5cm. • Breadth--5cm. • Thickness– 2.5 cm. • Body:cervix = 2:1 in adults • Body:cervix = 1:2 in children • Weight - about 30-40gm • Shape - Pyriform • The uterus is flattened from before backwards Normal Position & angulation Normal position – anteverted & anteflexed • Anteversion: is a forward angle between axis of cervix & that of vagina making an angle of 90 degree at external os of cervix • Anteflexion: is a forward angle between the body of the uterus & cervix at isthmus making an angle of 125 degree at internal os of cervix. Parts of uterus 1. Fundus 2. Body 3. Cervix 1. Fundus • The part of the body lies above the entrance of the uterine tube is known as the fundus. • It is convex like a dome. • Fundus does not contain cavity 2. Body • Extends from fundus to internal os • Contains uterine cavity • Body has following features • Ant. / vesical surface • Post. / intestinal surface • Lateral border • Lateral angle or cornua • Uterine cavity 2. Body – relations • Ant. / vesical surface • The bladder • Flat & covered with peritoneum upto isthmus • Forms vesico-uterine pouch. • Post. / intestinal surface • convex & covered with peritoneum. • Related to the sigmoid colon & coils of small intestine • Forms recto-uterine pouch or pouch of Douglas. 2. Body – relations • Lateral border • Convex, non peritoneal. • Related to uterine vessels. • Provides attachment to the broad ligament (fold of peritoneum stretches from the margins of the uterus to the lateral wall of the pelvis). 2. Body – relations • Lateral angle or cornua • Angle made by junction of fundus & body • 3 structures attached to the cornua 1. The uterine tube 2. The round ligament of the uterus (antero-inferior) 3. The ligament of the ovary (postero-inferiorly) 2. Body - Uterine cavity • Triangular on coronal section • Vertical slit on sagittal section • Base is formed by fundus & apex by internal os that continues with cervical canal 3. Cervix • It is more fixed & lower cylindrical part, lies below the isthmus • Cervix projects into vagina so divides into 1. Supra-vaginal part above 2. Vaginal part below • Isthmus (corresponds with internal os) • An area 4-5 mm in length that lies between anatomical internal os above, & histological internal os below that is lined by low columnar epithelium & few glands. • The isthmus expands during pregnancy forming the lower uterine segment (10 cm) during the last trimester. 3. Cervix – Supra-vaginal part Relations • Anteriorly: • Non peritoneal & related to posterior surface or base of urinary bladder. • Posteriorly: • The pouch of Douglas with coils of ileum, sigmoid colon & peritoneal Applied- Recto-uterine (Douglas) pouch. • This pouch separate it from the rectum. It is most dependent part. • Collection of pus or blood is drained by incision from posterior fornix. 3. Cervix – Supra-vaginal part Relations • Laterally: • ureter is crossed by the uterine artery (i.e. ureter below the uterine artery). • The uterosacral, cardinal, and pubocervical ligaments are attached to its posterior, lateral, and anterior surfaces respectively. 3. Cervix – vaginal part • Anteriorly: Cervix projects into • Anterior fornix of vagina. vagina & space • Posteriorly: between it & • Posterior fornix. vaginal wall are • Laterally: called vaginal • Lateral fornix of vagina. fornices 3. Cervix – cervical canal • Shape--fusiform • It communicates • above with uterine cavity at internal os • below with the vagina at the external os. • Mucosal membrane of the cervical canal is thrown into folds which resembles branches of a tree known as arbor vitae uteri 3. Cervix – cervical canal Coronal section TS Supports of uterus • Uterus is supported & prevented from prolapse by number of factors which are chiefly • Muscular supports 1. Pelvic diaphragm 2. Perineal body 3. Urethral sphincter mechanism • Fibromuscular or mechanial supports 1. Uterine axis 2. Round ligament 3. Utero-sacral ligament True ligaments 4. Transverse cervical ligament 5. Pubo-cervical ligament 23 Fibromuscular supports 1. Uterine axis In retroversion the fundus and body of the uterus are bent backward on the vagina leads to prolapse Fibromuscular support 2. Round ligament • A fibromuscular ligament extends from lateral angle of uterus and runs in inguinal canal attaches to labium majus. (remnant of Gubernaculum of ovary). • It pulls the uterus forwards and maintains anteversion position 3. Uterosacral ligament • from cervix to sacral vertebra (S2,S3). • Keep cervix braced backwards against forward pull of round ligament These two ligaments maintains the uterine axis Fibromuscular support 4. Transverse cervical/ cardianl/Mackenrodt’s ligament • Extends from lateral side of cervix to lateral pelvic wall • Prevents downward displacement of cervix & keeps cervix in median position. 5. Pubocervical ligament • Extends from cervix to pubic bone. Counteracts traction of uterosacral ligament Muscular supports 1. Pelvic diaphragm • Levator ani & coccygeus forms pelvic diaphragm that fix the perineal body, supports pelvic viscera & resists intra- abdominal pressure Pelvic diaphragm Prevents any prolapse through pelvic floor 2.Perineal body • Fibromuscular node, to which muscles are attached. • Lies 1.25cm infront of anal margin & anchor for pelvic diaphragm & maintains integrity of pelvic floor 3.Muscles of urogenital diaphragm • Formed by sphincter urethrae along with deep transverse perineal muscles Peritoneal ligaments These are mere PERITONEAL FOLDS which do not provide any SUPPORT TO UTERUS Allow the movements & give passage to vessels & ligments Also called as False ligaments • Broad ligament • Uterovesical fold or anterior ligament • Rectovaginal fold or posterior ligament The broad ligament A double sheet of peritoneum that extends from the lateral border of the uterus to the lateral pelvic wall. Parts; • Mesovarium – connects ovary to post. surface Contents of the Broad Ligament Clinical aspect - uterus • Prolapse of uterus • Hysteroscopy • Fibroids • Caesarean section: surgical procedure for delivering the baby by cutting open the abdomen and uterus in cases where vaginal delivery is not possible. • IUCD • Endometriosis VAGINA • Organ of copulation/lower part of birth canal • A fibromuscular tube from vulva to cervix extending upward & backwards. • Length: • anterior wall is 7-8cm • posterior wall is 9-10cm • Vaginal Fornices: • The cervix projects in the upper blind end of the vagina that forms a pouch (vaginal pouch) around the cervix and is divided into four fornices : two lateral, anterior and posterior (deeper) fornices. Relations of the Vagina Hymen is mucous fold situated close to external orifice of vagina in virgin Blood Supply of uterus & vagina Arterial Supply of uterus & vagina Uterus • Chiefly by uterine arteries; branch of anterior division of internal iliac artery. • Uterine aretry at base of the broad ligament, crossing above the ureter 1/2 an inch lateral to the supravaginal cervix. • tortuous & parallel to lateral border of the uterus • end by anastomosing with branches of the ovarian arteries • Partly by ovarian A. • Gives branches to : Vagina, medial 2/3rd of tube, ovary, ureter Vagina • The vaginal artery (from internal iliac artery) • Additional branches from: • vaginal branches from uterine artery. • Middle rectal artery • Internal pudendal artery Venous drainage of uterus & vagina Uterus • Vein forms a plexus along lateral border of uterus • Drains into the uterine, ovarian and vaginal veins into internal iliac vein. Vagina • A plexus around the vagina (the vaginal plexus), drain into the internal iliac vein by veins that accompany their corresponding arteries. Nerve supply of uterus & vagina • Sympathetic • from spinal nerves T12 ,L1 for uterus & L1-2 for vagina inferior hypogastric plexus uterovaginal plexuseuterus & vagina • causes uterine contraction & vasoconstriction • Parasympathetic • from S2,3,4 • causes inhibition & vasodilatation • Nerve supply of the vagina: • Upper 2/3 is insensitive to pain, touch & temperature but sensitive to stretch. • Lower 1/3 is sensitive to touch. Pudendal nerve gives sensory fibres to the lower vagina. Lymphatic drainage of uterus & vagina • is clinically important because uterine cancer spreads through lymphatics Most common cancer in the female Cervical cancer Applied Anatomy • Vaginal Prolapse: Weakness of the vaginal supports (ligaments, fascia and muscles) may lead to: • Prolapse of anterior vaginal wall drags bladder (cystocele) & urethra(urethrocele), • posterior vaginal wall (rectocele), Vaginal examination • Inspection ; speculum examination • Palpation • by per vagina