Uterus 

Introduction of Uterus :-

  • Uterus is a pyriform hollow muscular organ of female reproductive system which is situated between urinary bladder(Anterior) and rectum(posterior). 
  • Uterus is a secondary sex organ and synonyms with metro and hystero. 
  • Uterus is place where fetus develops by and also called womb. 
  • in pregnancy when uterus is grow due to fetus implantation than a women able to feel his uterus
  • Uterus is connected to vagina by cervix

Uterus diagram
Fig. 1 midsagittal section of uterus

    Size of uterus :-

    Length 7.5CM(in pregnancy it increases 5times 35to40cm) 
    Width 3.5CM
    Thickness 2.5CM
    Weight 50 to 80gm (avarage 60gm)
    In pregnancy 900 to 1000gm due to hyperplasia. 

    Position of uterus :-

    Uterus is situated in two positions in pelvic area
    • Anteversion (at 90° angle with Vagina) 
    • Anteflexion (at 120° angle with own body of uterus
    Uterus
    Fig. 2 position of uterus

    Types of uterus :- 

    1.Duplex :-

    • In duplex,uterus horns are completely separated and have separate cervix opening into vagina and one fallopian tube it is found in kangaroo , rabbits , hares etc. 

    2.Bipartite :-

    • In bipartite,uterus horns are largely separate and have a single cervix opening into vagina. It found in cats and horses etc. 

    3.Bicornuate :-

    • In bicornuate,uterus appears like a heart-shaped the lower parts are fused into a single cervix
    • A bicornuate uterus is a type of congenital uterine malformation and it found in elephant, dolphins, dogs etc. 

    4.Simplex :-

    • In simplex,uterus consisting of a single cavity and found in higher primates(human and chimpanzees. 

    Relations of uterus :-

    Anterior relation of uterus :-

    • Above internal OS uterovesical pouch 
    • Below internal OS base of the bladder

    Posterior relation of uterus :-

    It is covered with peritoneum and forms the anterior wall of pouch of Douglas containing coils of intestine. 

    Layer of uterus :-

    1.Perimetrium :- 

    • It is outer most layer of serous (peritoneum) coat which is lies over the fundus and it is anteriorly makes a folds over the urinary urinary bladder to form vesico-uterine pouch. 
    • Posteriorly it also makes a folds known as Recto-uterine pouch that is infront of rectum and behind the uterus . (See in fig. 1) 
    • The Recto-uterine pouch is also known as cul-de-sac or pouch of Douglas. 
    • In ectopic pregnancy fluid is aspirated from pouch of Douglas, called culdocentesis. 

    2.Myometrium :-

    • Myometrium layer of uterus is the thickest layer of smooth muscles fibers which is divided into three types as follows.....
    (A) Outer layer :- 
    • This layer of myometrium consisting of longitudinal muscles fibers. 
    (B) Middle layer :-
    • It is also known as living liguture of uterus because the oxytocin (muscular contracter) contract the muscles fibers and compress the uterine artery, which is lies in figur of eight muscles fibers and prevent from postpartum hemorrhage. 
    (C) Inner layer :-
    • This layer of myometrium consisting circular muscles fibers. 

    3.Endometrium :-

    • Endometrium is inner most layer of uterus and mucous membrane which is consist of columnar epithelium. 
    • It is consist of two layer, these are
    (A) stratum functionalis or functional layer:- It present in uterine cavity and shed off during menstruation. 
    (B) stratum basalis or basal layer :-
    A permanant layer which regulate the regeneration of new stratum functionalis layer after menstruation. 

    Parts of uterus :-

    Uterus diagram
    Fig. 3 Coronal section of uterus

    •The uterus has three parts these are

    1.Corpus :-

    Corpus is a 5cm long part of uterus that has two parts 
    (A) Fundus :- fundus is a most upper part of corpus that lies above the opening of uterine tube of uterine tube in dome shaped. The length of fundus is about 1.5cm.

    (B) Body cavity :- Body cavities is a triangular part and lies between isthmus and opening of uterine tube. 
    • The internal triangular 6-7cm part called uterine cavity. 
    • Body cavity is about 3.5cm long part
    • The implantation of fetus also occur in this part of corpus. 

    2.Isthmus :-

    • It is a narrowing part of the uterus that is situated between body and cervix. 
    • It is limited to above by anatomical OS (OS mean  mouth like opening) and below by histological internal OS (Aschoff) 
    • The length of isthmus is about 0.5cm long. 

    3.Cervix :-

    • Cervix is a cylindrical part of uterus which is also known as neck of uterus and it is measure about 2.5cm long. 
    • It is located between isthmus and internal OS and end with external OS and continue with vagina. 
    • It may be torn in child birth, especially in primigravida (a woman who is pregnant for the for the first time. 
    • It secrets 20-60ml/day cervical mucus which is favorable during ovulation and later become thick to prevent entry of sperm by forming cervical plug. 
    • The cervix part of the uterus has two parts, endocervix(supravaginal part) and ectocervix(vaginal part). 

    Development of uterus :-

    • The uterus is developed from the fused vertical part of the two mullerian ducts. 

    Functions of uterus :-

    • It is Provide a place to fetus for implantation
    • Providing nutrition to fetus 
    • Maintain menstruation cycle
    • Expulsion of fetus

    Blood supply of uterus :-

    Atrial supply :-

    • The blood supply is from the uterine arteries one each side. The artery from the anterior division of the internal iliac or in common with superior vesical artery. 
    • The other sources are ovarian and vaginal artery. 

    Venous supply :-

    • The venous channel correspond to the atrial course and drain into internal iliac veins. 

    Uterus problem :-

    Uterine fibroids :- 

    • It is also known as uterus myoma 
    • It is a condition of non-cancerous growth of uterus that can develop in child bearing age. 
    • Uterine fibroids occur due to the some risk factor like obesity, family history, early onset of puberty. 
    • Some symptoms are occur during uterine fibroids like pain in abdomen, abnormal menstruation, prolonged priods etc. 
    • The treatment of uterine fibroids included progestin IUD (a device that is placed inside your womb for prevent pregnancy by realising progesterone hormone.) and some medication such as oral contraceptives, NSAIDs 
    • If uterine fibroids can not treated by medication than your doctor suggest surgical treatment that includes hysterectomy (surgical removal of your  womb) , uterine myomectomy (surgical removal of non-cancerous tumor from uterus). 

    Endometriosis :- 

    • Endometriosis is a disorder in which a tissue similar to the tissue that form inside of uterus but in location outside the uterus. 

    Uterine prolapse :-

    • Uterine prolapse, it is a condition of displacement of the part of uterus especially downward into vagina and some time it also protrude from orifice. 

    Click here to get pdf of uterus

    Some others uterus problem :-

    • HIV/AIDS
    • Sexual violence
    • Interstitial cystitis 
    • Gynecologic cancer
    • Uterine tuberculosis
    I hope you all like our article on introduction of uterus, it's type and parts of uterus, some problem of uterus. Please watch above video on uterus to better understand. 

    Thank you.