All Topics  
Uterus

 

 
   Email Print
   Bookmark   Link
 

 

Uterus
 
 
  Topics Uterus Topic Home

The uterus (Latin word for womb) is a major female
Female

Female is the sex of an organism, or a part of an organism, which produces mobile ovum . The ova are defined as the larger gametes in a heterogamous reproduction system, while the smaller, usually motile gamete, the spermatozoon, is produced by the male....
 hormone-responsive reproductive sex
Sex

In biology, sex is a process of combining and mixing genetics traits, often resulting in the specialization of organisms into male and female types ....
 organ
Organ (anatomy)

In biology, an organ is a biological tissue that performs a specific function or group of functions. Usually there is a main tissue and sporadic tissues....
 of most mammal
Mammal

Mammals are a class of vertebrate animals whose name is derived from their distinctive feature, mammary glands, with which they feed their young....
s, including human
Human

A human being, also human or man, is a member of a species of bipedalism primates in the family Hominidae . Mitochondrial DNA evidence indicates that modern humans originated in east Africa about 200,000 years ago....
s. It is within the uterus that the fetus
Fetus

A fetus is a developing mammal or other viviparous vertebrate, after the embryonic stage and before childbirth. The plural is fetuses, or sometimes feti....
 develops during gestation
Gestation

Gestation is the carrying of an embryo or fetus inside a female viviparous animal. Mammals during mammalian pregnancy can have one or more gestations at the same time ....
. The term uterus is used consistently within the medical and related professions; the Germanic term, womb is more common in everyday usage. The plural of uterus is uteruses or uteri.

One end, the cervix
Cervix

The cervix is the lower, narrow portion of the uterus where it joins with the top end of the vagina. It is cylindrical or conical in shape and protrudes through the upper anterior vaginal wall....
, opens into the vagina
Vagina

The vagina is a fibromuscular cylinder tract leading from the uterus to the exterior of the body in female placental mammals and marsupials, or to the cloaca in female birds, monotremes, and some reptiles....
; the other is connected on both sides to the Fallopian tubes.

uterus provides structural integrity and support to the bladder
Bladder

Bladder may refer to:* A bladder is a pouch or other flexible enclosure with waterproof or gasproof walls* Gas bladder, an internal organ that contributes to the ability of a fish to control its buoyancy...
, bowel, pelvic bones and organs.






Discussion
Ask a question about 'Uterus'
Start a new discussion about 'Uterus'
Answer questions from other users
Full Discussion Forum



Recent Posts

My name is Shikha i found mycobacterium tuberculosis problem in Uterus. I am 29 year old recently go...








Encyclopedia


The uterus (Latin word for womb) is a major female
Female

Female is the sex of an organism, or a part of an organism, which produces mobile ovum . The ova are defined as the larger gametes in a heterogamous reproduction system, while the smaller, usually motile gamete, the spermatozoon, is produced by the male....
 hormone-responsive reproductive sex
Sex

In biology, sex is a process of combining and mixing genetics traits, often resulting in the specialization of organisms into male and female types ....
 organ
Organ (anatomy)

In biology, an organ is a biological tissue that performs a specific function or group of functions. Usually there is a main tissue and sporadic tissues....
 of most mammal
Mammal

Mammals are a class of vertebrate animals whose name is derived from their distinctive feature, mammary glands, with which they feed their young....
s, including human
Human

A human being, also human or man, is a member of a species of bipedalism primates in the family Hominidae . Mitochondrial DNA evidence indicates that modern humans originated in east Africa about 200,000 years ago....
s. It is within the uterus that the fetus
Fetus

A fetus is a developing mammal or other viviparous vertebrate, after the embryonic stage and before childbirth. The plural is fetuses, or sometimes feti....
 develops during gestation
Gestation

Gestation is the carrying of an embryo or fetus inside a female viviparous animal. Mammals during mammalian pregnancy can have one or more gestations at the same time ....
. The term uterus is used consistently within the medical and related professions; the Germanic term, womb is more common in everyday usage. The plural of uterus is uteruses or uteri.

One end, the cervix
Cervix

The cervix is the lower, narrow portion of the uterus where it joins with the top end of the vagina. It is cylindrical or conical in shape and protrudes through the upper anterior vaginal wall....
, opens into the vagina
Vagina

The vagina is a fibromuscular cylinder tract leading from the uterus to the exterior of the body in female placental mammals and marsupials, or to the cloaca in female birds, monotremes, and some reptiles....
; the other is connected on both sides to the Fallopian tubes.

Function

The uterus provides structural integrity and support to the bladder
Bladder

Bladder may refer to:* A bladder is a pouch or other flexible enclosure with waterproof or gasproof walls* Gas bladder, an internal organ that contributes to the ability of a fish to control its buoyancy...
, bowel, pelvic bones and organs. The uterus helps separate and keep the bladder in its natural position above the pubic bone and the bowel in its natural configuration behind the uterus. The uterus is continuous with the cervix
Cervix

The cervix is the lower, narrow portion of the uterus where it joins with the top end of the vagina. It is cylindrical or conical in shape and protrudes through the upper anterior vaginal wall....
, which is continuous with the vagina
Vagina

The vagina is a fibromuscular cylinder tract leading from the uterus to the exterior of the body in female placental mammals and marsupials, or to the cloaca in female birds, monotremes, and some reptiles....
, much in the way that the head is continuous with the neck, which is continuous with the shoulders. It is attached to bundles of nerves, and networks of arteries and veins, and broad bands of ligaments such as round ligaments, cardinal ligaments
Cardinal ligaments

The cardinal ligaments are bands of fibromuscular fascia that attach the cervix and vagina to the pelvic walls at the ischial spine, lending support to the uterus. It belongs to the major ligaments of the uterus....
, broad ligaments, and uterosacral ligaments
Uterosacral ligaments

The uterosacral ligaments belongs to the major ligaments of uterus.The rectouterine folds contain a considerable amount of fibrous tissue and non-striped muscular fibers which are attached to the front of the sacrum and constitute the uterosacral ligaments....
 .

The uterus is essential in sexual response by directing blood flow to the pelvis
Pelvis

The pelvis or pelvic girdle is the irregular bone structure located at the base of the spine . In the adult human, it is formed by the sacrum and the coccyx, the caudal part of the axial skeleton, and a pair of hip bones, part of the appendicular skeleton or human leg....
 and to the external genitalia, including the ovaries, vagina
Vagina

The vagina is a fibromuscular cylinder tract leading from the uterus to the exterior of the body in female placental mammals and marsupials, or to the cloaca in female birds, monotremes, and some reptiles....
, labia, and clitoris
Clitoris

The clitoris is a sex organ that is present only in female mammals. In humans, the visible button-like portion is located near the anterior junction of the labia minora, above the opening of the urethra and vagina....
. The uterus is needed for uterine orgasm
Orgasm

An orgasm is the conclusion of the Human sexual response cycle#Plateau phase of Human sexual response cycle, and may be experienced by both males and females....
 to occur.

The reproductive function of the uterus is to accept a fertilized ovum
Ovum

An ovum is a haploid female reproductive cell or gamete. Both animals and embryophytes have ova. The term ovule is used for the young ovum of an animal, as well as the plant structure that carries the female gametophyte and egg cell and develops into a seed after fertilization....
 which becomes implanted into the endometrium
Endometrium

The endometrium is the inner membrane of the mammalian uterus....
, and derives nourishment from blood vessels which develop exclusively for this purpose. The fertilized ovum becomes an embryo
Embryo

An embryo is a multicellular organism ploidy eukaryote in its earliest stage of development, from the time of first cell division until birth, Egg , or germination....
, develops into a fetus
Fetus

A fetus is a developing mammal or other viviparous vertebrate, after the embryonic stage and before childbirth. The plural is fetuses, or sometimes feti....
 and gestates until childbirth
Childbirth

Childbirth is the culmination of a human pregnancy or gestation period with the delivery of one or more newborn infants from a woman's uterus. The process of normal human childbirth is categorized in three stages of labour: the shortening and dilation of the cervix, descent and delivery of the infant, and delivery of the placenta.....
. Due to anatomical barriers such as the pelvis
Pelvis

The pelvis or pelvic girdle is the irregular bone structure located at the base of the spine . In the adult human, it is formed by the sacrum and the coccyx, the caudal part of the axial skeleton, and a pair of hip bones, part of the appendicular skeleton or human leg....
, the uterus is pushed partially into the abdomen due to its expansion during pregnancy. Even during pregnancy the mass of a human uterus amounts to only about a kilogram (2.2 pounds).

Forms in mammals

In mammals, the four main forms in which it is found are: Bipartite : Found in ungulates (deer, moose, elk etc.), and in carnivores (cats, and dogs). Bicornuate : Found in pigs. Simplex : Found in humans, other primates and horses. Duplex : Found in rodents (such as mice, rats and guinea pigs), marsupials and lagomorpha (rabbits and hares).

Anatomy

The uterus is located inside the pelvis
Pelvis

The pelvis or pelvic girdle is the irregular bone structure located at the base of the spine . In the adult human, it is formed by the sacrum and the coccyx, the caudal part of the axial skeleton, and a pair of hip bones, part of the appendicular skeleton or human leg....
 immediately dorsal
Dorsum (biology)

In anatomy, the dorsum is the upper side of animals that typically run, fly, or swim in a horizontal position, and the back side of animals that walk upright....
 (and usually somewhat rostral
Rostral

Rostral can refer to:* Anatomical terms of location#Directions, Top or cephaled, as opposed to caudal or down.* Rostral bone* Rostral column, a monumental scaled column, frequently decorated with ship bows...
) to the urinary bladder
Urinary bladder

In anatomy, the urinary bladder is a solid, muscle, and distensible organ that sits on the pelvic floor in mammals. It is the organ that collects urine excreted by the kidneys prior to disposal by urination....
 and ventral to the rectum
Rectum

The rectum is the final straight portion of the large intestine in some mammals, and the Gastrointestinal tract in others, terminating in the anus....
. Outside of pregnancy
Pregnancy

Pregnancy is the carrying of one or more offspring, known as a fetus or embryo, inside the uterus of a female. In a pregnancy, there can be multiple gestations, as in the case of twins or Multiple birth....
, its size in humans is several centimeters in diameter. The uterus is a pear shaped muscular organ which can be divided anatomically into four segments: The fundus, corpus, cervix and the internal os
Internal orifice of the uterus

The internal orifice of the uterus is an interior narrowing of the uterine cavity. It corresponds to a slight constriction known as the isthmus that can be observed on the surface of the uterus about midway between the apex and base....
.

Regions

From outside to inside, the path to the uterus is as follows:
  • Vulva
    Vulva

    The vulva refers to the external sex organ of the female. In colloquial speech, the term vagina is often used to refer to the female genitals generally, although, strictly speaking, the vagina is a specific internal structure, whereas the vulva is the whole exterior genitalia....
  • Vagina
    Vagina

    The vagina is a fibromuscular cylinder tract leading from the uterus to the exterior of the body in female placental mammals and marsupials, or to the cloaca in female birds, monotremes, and some reptiles....
  • Cervix
    Cervix

    The cervix is the lower, narrow portion of the uterus where it joins with the top end of the vagina. It is cylindrical or conical in shape and protrudes through the upper anterior vaginal wall....
     uteri - "neck of uterus"
    • External orifice of the uterus
      External orifice of the uterus

      The external orifice of the uterus is a small, depressed, somewhat circular aperture on the rounded extremity of the Vaginal portion of cervix....
    • Canal of the cervix
      Canal of the cervix

      In the anatomy of the female reproductive system, the canal of the cervix is the spindle-shaped, flattened canal of the cervix, the neck of the uterus....
    • Internal orifice of the uterus
      Internal orifice of the uterus

      The internal orifice of the uterus is an interior narrowing of the uterine cavity. It corresponds to a slight constriction known as the isthmus that can be observed on the surface of the uterus about midway between the apex and base....
  • corpus uteri - "Body of uterus"
    • Cavity of the body of the uterus
    • Fundus (uterus)
      Fundus (uterus)

      The fundus of the uterus is the top portion, opposite from the cervix.Fundal height, measured from the top of the pubic bone, is routinely measured in pregnancy to determine growth rates....


Layers

The layers, from innermost to outermost, are as follows: Endometrium
Endometrium

The endometrium is the inner membrane of the mammalian uterus....
 : The lining of the uterine cavity is called the "endometrium." It consists of the functional endometrium and the basal endometrium from which the former arises. In most mammals, including humans, the endometrium builds a lining periodically which is shed or reabsorbed if no pregnancy
Pregnancy

Pregnancy is the carrying of one or more offspring, known as a fetus or embryo, inside the uterus of a female. In a pregnancy, there can be multiple gestations, as in the case of twins or Multiple birth....
 occurs. Shedding of the functional endometrial lining in humans is responsible for menstrual bleeding
Menstruation

See also "Mensuration", a term sometimes used to describe Measurement, particularly in the context of forestry.Menstruation is the shedding of the uterine lining ....
 (known colloquially as a woman's "period") throughout the fertile years of a female and for some time beyond. In other mammals there may be cycles set as widely apart as six months or as frequently as a few days. Myometrium
Myometrium

The myometrium is the middle layer of the uterus wall consisting of smooth muscle cells and supporting stromal and vascular tissue.The inner layer of the uterine wall is the endometrium or uterine lining, and the outer layer the serosa or perimetrium....
 : The uterus mostly consists of smooth muscle
Smooth muscle

Smooth muscle is a type of non-striated muscle, found within the tunica media layer of large and small arteries and veins, the urinary bladder, uterus, male and female reproductive tracts, gastrointestinal tract, respiratory tract, the ciliary muscle, and iris of the eye....
, known as "myometrium." The innermost layer of myometrium is known as the junctional zone, which becomes thickened in adenomyosis
Adenomyosis

Adenomyosis is a medical condition characterized by the presence of ectopic endometrium within the uterus .The condition is typically found in women between the ages of 35 and 50....
. Perimetrium
Perimetrium

The perimetrium is the outer serosa layer of the uterus, equivalent to peritoneum.External links - "Mammal, uterus "...
 : The loose surrounding tissue is called the "perimetrium." Peritoneum
Peritoneum

In higher vertebrates, the peritoneum is the serous membrane that forms the lining of the abdomen — it covers most of the intra-abdominal organs....
 : The uterus is surrounded by "peritoneum."

Support

The uterus is primarily supported by the pelvic diaphragm and the urogenital diaphragm
Urogenital diaphragm

Older texts have asserted the existence of an "urogenital diaphragm", which was described as a layer of the pelvis that separates the deep perineal sac from the upper pelvis, lying between the inferior fascia of the urogenital diaphragm and superior fascia of the urogenital diaphragm....
. Secondarily, it is supported by ligaments and the peritoneum (broad ligament of uterus)

Major ligaments
It is held in place by several peritoneal
Peritoneum

In higher vertebrates, the peritoneum is the serous membrane that forms the lining of the abdomen — it covers most of the intra-abdominal organs....
 ligament
Ligament

Ligaments connect bone to bone. In anatomy, the term ligament is used to denote three different types of structures:# Fibrous Tissue that connects bones to other bones....
s, of which the following are the most important (there are two of each):

Name From To
uterosacral ligament the posterior cervix the sacrum of pelvis
Pelvis

The pelvis or pelvic girdle is the irregular bone structure located at the base of the spine . In the adult human, it is formed by the sacrum and the coccyx, the caudal part of the axial skeleton, and a pair of hip bones, part of the appendicular skeleton or human leg....
cardinal ligaments
Cardinal ligaments

The cardinal ligaments are bands of fibromuscular fascia that attach the cervix and vagina to the pelvic walls at the ischial spine, lending support to the uterus. It belongs to the major ligaments of the uterus....
 		 the side of the cervix the ischial spines
pubocervical ligament  


Other named ligaments near the uterus, i.e. the broad ligament, the round ligament, the suspensory ligament of the ovary, the infundibulopelvic ligament, have no role in the support of the uterus.

Position

Under normal circumstances the uterus is both "anteflexed" and "anteverted." The meaning of these terms are described below:
Distinction More common Less common
Position tipped "anteverted": tipped forward "retroverted
Retroverted uterus

A retroverted uterus is a uterus that is tilted backwards instead of forwards. This is in contrast to the slightly "anteverted" uterus that most women have, which is tipped forward toward the Urinary bladder, with the anterior end slightly concave....
": tipped backwards
Position of fundus "anteflexed": the fundus is pointing forward relative to the cervix "retroflexed": the fundus is pointing backwards


Development

The bilateral Müllerian duct
Müllerian duct

The M?llerian ducts are paired ducts of the embryo which run down the lateral sides of the urogenital ridge and terminate at the mullerian tubercle in the primitive urogenital sinus....
s form during early fetal life. In males, MIF
Anti-müllerian hormone

Anti-M?llerian hormone also known as AMH is a protein which in humans is encoded by the AMH gene. It has also been called M?llerian inhibiting factor , M?llerian inhibiting hormone , and M?llerian inhibiting substance ....
 secreted from the testes leads to their regression. In females these ducts give rise to the Fallopian tubes and the uterus. In humans the lower segments of the two ducts fuse to form a single uterus, however, in cases of uterine malformation
Uterine malformation

A uterine malformation is the result of an abnormal development of the Mullerian duct during embryogenesis. Symptoms range from amenorrhea, infertility, recurrent pregnancy loss, and pain, to normal functioning depending on the nature of the defect....
s this development may be disturbed. The different uterine forms in various mammals are due to various degrees of fusion of the two Müllerian ducts.

Sexual response


Stimulation of the uterus can result in an intense orgasm
Orgasm

An orgasm is the conclusion of the Human sexual response cycle#Plateau phase of Human sexual response cycle, and may be experienced by both males and females....
.

Pathology

Some pathological
Pathology

Pathology is the study and diagnosis of disease through examination of Organ , tissue , bodily fluids and whole bodies . The term also encompasses the related science study of disease processes, called General pathology....
 states include:
  • Prolapse
    Prolapse

    Prolapse literally means "To fall out of place." In medicine, prolapse is a condition where organs, such as the uterus, fall down or slip out of place....
     of the uterus
  • Carcinoma of the cervix – malignant neoplasm
  • Carcinoma of the uterus – malignant neoplasm
  • Fibroid
    Uterine fibroids

    Uterine fibroids are benign tumors which grow from the muscle layers of the uterus. They are the most common benign neoplasm in females. Often asymptomatic, they cause symptoms in about 25% of white and 50% of black women ....
    s – benign neoplasms
  • Adenomyosis
    Adenomyosis

    Adenomyosis is a medical condition characterized by the presence of ectopic endometrium within the uterus .The condition is typically found in women between the ages of 35 and 50....
     – ectopic growth of endometrial tissue within the myometrium
  • Pyometra
    Pyometra

    Pyometra is a disease of the uterus most commonly seen in female dogs , but also seen in female cats , rabbits, ferrets, rats and guinea pigs. Pyometra is an important disease to be aware of for any dog owner because of the sudden nature of the disease and the deadly consequences if left untreated....
     – infection of the uterus, most commonly seen in dog
    Dog

    The dog is a domesticated subspecies of the Gray Wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties....
    s
  • Uterine malformation
    Uterine malformation

    A uterine malformation is the result of an abnormal development of the Mullerian duct during embryogenesis. Symptoms range from amenorrhea, infertility, recurrent pregnancy loss, and pain, to normal functioning depending on the nature of the defect....
    s mainly congenital malformations including Uterine Didelphys
    Uterine Didelphys

    Uterus didelphys represents a uterine malformation where the uterus is present as a paired organ as the embryogenetic fusion of the mullerian ducts failed to occur....
    , bicornuate uterus and septate uterus. It also includes congenital absence of the uterus Rokitansky Syndrome
  • Asherman's syndrome
    Asherman's syndrome

    Asherman's syndrome, also called "uterine synechiae" or intrauterine adhesions, presents a condition characterized by the presence of scars within the uterine cavity....
    , also known as intrauterine adhesions occurs when the basal layer of the endometrium is damaged by instrumention (eg. D&C
    D&C

    D&C may stand for:* Doctrine and Covenants, part of the scripture of Mormonism* Dilation and curettage, a medical procedure involving the dilation of the cervix to remove uterine contents...
    ) or infection (eg. endometrial tuberculosis
    Tuberculosis

    Tuberculosis is a common and often deadly infectious disease caused by mycobacterium, mainly Mycobacterium tuberculosis . Tuberculosis usually attacks the lungs but can also affect the central nervous system, the lymphatic system, the circulatory system, the genitourinary system, the gastrointestinal system, bones, joints, and even the...
    ) resulting in endometrial scarring followed by adhesion formation which partially or completely obliterates the uterine cavity.


Additional images


See also

  • Hysterectomy Educational Resources and Services (HERS) Foundation
    Hysterectomy Educational Resources and Services (HERS) Foundation

    The Hysterectomy Educational Resources & Services Foundation is an independent non-profit international women?s health educational advocacy organization ....
  • Myometrium
    Myometrium

    The myometrium is the middle layer of the uterus wall consisting of smooth muscle cells and supporting stromal and vascular tissue.The inner layer of the uterine wall is the endometrium or uterine lining, and the outer layer the serosa or perimetrium....
  • Egg (ovum
    Ovum

    An ovum is a haploid female reproductive cell or gamete. Both animals and embryophytes have ova. The term ovule is used for the young ovum of an animal, as well as the plant structure that carries the female gametophyte and egg cell and develops into a seed after fertilization....
    )
  • Ovary
    Ovary

    The ovary is an ovum-producing reproductive organ, often found in pairs as part of the vertebrate female reproductive system. Ovaries in females are homology to testicle in males, in that they are both gonads and endocrine glands....
  • Menopause
    Menopause

    The Menopause is the permanent cessation of menstruation which occurs a considerable length of time before the end of the lifespan.The word was first applied to humans, and because of this it literally means the cessation of monthly cycles or menstrual cycles, from the Greek roots meno and pausis ....
  • Vulva
    Vulva

    The vulva refers to the external sex organ of the female. In colloquial speech, the term vagina is often used to refer to the female genitals generally, although, strictly speaking, the vagina is a specific internal structure, whereas the vulva is the whole exterior genitalia....
  • Vagina
    Vagina

    The vagina is a fibromuscular cylinder tract leading from the uterus to the exterior of the body in female placental mammals and marsupials, or to the cloaca in female birds, monotremes, and some reptiles....
  • Penis
    Penis

    The penis is an external sex organ of certain biologically male organisms, in both vertebrates and invertebrates.The penis is a reproductive organ, technically an intromittent organ, and for Eutheria, additionally serves as the external organ of urination....
  • Uterine glands
    Uterine glands

    In the uterus are the tube-like uterine glands, lined by ciliated columnar epithelium.They are of small size in the unimpregnated uterus, but shortly after impregnation become enlarged and elongated, presenting a contorted or waved appearance....
  • Uterine orgasm
    Uterine orgasm

    A uterine orgasm occurs due to stimulation and stretching of a woman's fornix, just above and below the cervix, near the Anterior Fornix Erogenous Zone, at the end of the vagina, which results in indirect contact with the uterus....


External links