Uterine malformation
Encyclopedia
A uterine malformation is a type of female genital malformation resulting from an abnormal development of the Müllerian duct
(s) during embryogenesis
. Symptoms range from amenorrhea, infertility
, recurrent pregnancy loss, and pain, to normal functioning depending on the nature of the defect.
) Classification distinguishes:
A uterine septum can be corrected by hysteroscopic surgery
.
An additional variation is the arcuate uterus
where there is a concave dimple in the uterine fundus within the cavity.
A rudimentary uterus is a uterine remnant not connected to cervix and vagina and may be found on the other side of an unicornuate uterus.
Patients with uterine abnormalities may have associated renal abnormalities including unilateral renal agenesis.
is largely derived from the Müllerian ducts, lack of fusion of the two ducts can lead to the formation of a vaginal duplication and lack of absorption of the wall between the two ducts will leave a residual septum
, leading to a "double vagina". This condition may be associated with a uterus didelphys or a uterine septum
. Since the condition is internal and usually asymptomatic, a person may not be aware of having a "double vagina." If necessary, the partition can be surgically corrected, however, there is no valid medical reason for such a procedure.
, pelvic MRI, or hysterosalpingography
. A hysterosalpingogram is not considered as useful due to the inability of the technique to evaluate the exterior contour of the uterus and distinguish between a bicornuate and septate uterus.
In addition, laparoscopy
and/or hysteroscopy
may be indicated.
In some patients the vagina
l development may be affected.
A uterine septum can be resected in a simple out-patient procedure that combines laparoscopy and hysteroscopy. This procedure greatly decreases the rate of miscarriage for women with this anomaly.
Müllerian duct
Müllerian ducts are paired ducts of the embryo that run down the lateral sides of the urogenital ridge and terminate at the Müllerian eminence in the primitive urogenital sinus. In the female, they will develop to form the Fallopian tubes, uterus, cervix, and the upper two-third of the vagina; in...
(s) during embryogenesis
Embryogenesis
Embryogenesis is the process by which the embryo is formed and develops, until it develops into a fetus.Embryogenesis starts with the fertilization of the ovum by sperm. The fertilized ovum is referred to as a zygote...
. Symptoms range from amenorrhea, infertility
Infertility
Infertility primarily refers to the biological inability of a person to contribute to conception. Infertility may also refer to the state of a woman who is unable to carry a pregnancy to full term...
, recurrent pregnancy loss, and pain, to normal functioning depending on the nature of the defect.
Prevalence
The prevalence of uterine malformation is estimated to be 6.7% in the general population, slightly higher (7.3%) in the infertility population, and significantly higher in a population of women with a history of recurrent miscarriages (16%).Types
The American Fertility Society (now American Society of Reproductive MedicineAmerican Society of Reproductive Medicine
The American Society for Reproductive Medicine is an organization that wants to advance the "art, science, and practice of reproductive medicine". It provides a forum for lay public, researchers, physicians and affiliated health workers through education, publications, and meetings...
) Classification distinguishes:
- Class I: Müllerian agenesisMullerian agenesisMüllerian agenesis is a congenital malformation in women characterised by a failure of the müllerian ducts to develop, resulting in a missing uterus and fallopian tubes and variable malformations of the upper portion of the vagina. It is the second most common cause of primary amenorrhea after...
(absent uterus).- Uterus is not present, vagina only rudimentary or absent. The condition is also called Mayer-Rokitansky-Kuster-Hauser syndrome. The patient with MRKH syndrome will have primary amenorrhea.
- Class II: Unicornuate uterusUnicornuate uterusA unicornuate uterus represents a uterine malformation where the uterus is formed from one only of the paired Müllerian ducts while the other Müllerian duct does not develop or only in a rudimentary fashion...
(a one-sided uterus).- Only one side of the Müllerian duct forms. The uterus has a typical "penis shape" on imaging systems.
- Class III: Uterus didelphys, also uterus didelphis (double uterus).
- Both Müllerian ducts develop but fail to fuse, thus the patient has a "double uterus". This may be a condition with a double cervix and a vaginal partition (v.i.), or the lower Müllerian system fused into its unpaired condition. See Triplet-birth with Uterus didelphys for a case of a woman having spontaneous birth in both wombs with twins.
- Class IV: Bicornuate uterusBicornuate uterusA bicornuate uterus or bicornate uterus, commonly referred to as a "heart-shaped" uterus, is a type of uterine malformation where two "horns" form at the upper part of the uterus.-Pathophysiology:A bicornuate uterus is formed during embryogenesis....
(uterus with two horns).- Only the upper part of that part of the Müllerian system that forms the uterus fails to fuse, thus the caudal part of the uterus is normal, the cranial part is bifurcated. The uterus is "heart-shaped".
- Class V: Septated uterus (uterine septum or partition).
- The two Müllerian ducts have fused, but the partition between them is still present, splitting the system into two parts. With a complete septum the vagina, cervix and the uterus can be partitioned. Usually the septum affects only the cranial part of the uterus. A uterine septum is the most common uterine malformation and a cause for miscarriageMiscarriageMiscarriage or spontaneous abortion is the spontaneous end of a pregnancy at a stage where the embryo or fetus is incapable of surviving independently, generally defined in humans at prior to 20 weeks of gestation...
s. It is diagnosed by medical image techniques, i.e. ultrasound or an MRI. MRI is considered the preferred modality due to its multiplanar capabilities as well as its ability to evaluate the uterine contour, junctional zone, and other pelvic anatomy. A hysterosalpingogram is not considered as useful due to the inability of the technique to evaluate the exterior contour of the uterus and distinguish between a bicornuate and septate uterus.
- The two Müllerian ducts have fused, but the partition between them is still present, splitting the system into two parts. With a complete septum the vagina, cervix and the uterus can be partitioned. Usually the septum affects only the cranial part of the uterus. A uterine septum is the most common uterine malformation and a cause for miscarriage
A uterine septum can be corrected by hysteroscopic surgery
Hysteroscopy
Hysteroscopy is the inspection of the uterine cavity by endoscopy with access through the cervix. It allows for the diagnosis of intrauterine pathology and serves as a method for surgical intervention .-Method:...
.
- Class VI: DESDiethylstilbestrolDiethylstilbestrol is a synthetic nonsteroidal estrogen that was first synthesized in 1938. Human exposure to DES occurred through diverse sources, such as dietary ingestion from supplemented cattle feed and medical treatment for certain conditions, including breast and prostate cancers...
uterus.- The uterine cavity has a "T-shape" as a result of fetal exposure to diethylstilbestrolDiethylstilbestrolDiethylstilbestrol is a synthetic nonsteroidal estrogen that was first synthesized in 1938. Human exposure to DES occurred through diverse sources, such as dietary ingestion from supplemented cattle feed and medical treatment for certain conditions, including breast and prostate cancers...
.
- The uterine cavity has a "T-shape" as a result of fetal exposure to diethylstilbestrol
An additional variation is the arcuate uterus
Arcuate uterus
The arcuate uterus is a form of a uterine anomaly or variation where the uterine fundus displays a concave contour towards the uterine cavity. Normally the fundus of the uterus is straight or convex on anterior-posterior imaging but in the arcuate uterus it dips into the cavity and may form a small...
where there is a concave dimple in the uterine fundus within the cavity.
A rudimentary uterus is a uterine remnant not connected to cervix and vagina and may be found on the other side of an unicornuate uterus.
Patients with uterine abnormalities may have associated renal abnormalities including unilateral renal agenesis.
"Double vagina"
As the vaginaVagina
The vagina is a fibromuscular tubular 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. Female insects and other invertebrates also have a vagina, which is the terminal part of the...
is largely derived from the Müllerian ducts, lack of fusion of the two ducts can lead to the formation of a vaginal duplication and lack of absorption of the wall between the two ducts will leave a residual septum
Septum
In anatomy, a septum is a wall, dividing a cavity or structure into smaller ones.-In human anatomy:...
, leading to a "double vagina". This condition may be associated with a uterus didelphys or a uterine septum
Uterine septum
A uterine septum is a form of a congenital malformation where the uterine cavity is partitioned by a longitudinal septum; the outside of the uterus has a normal typical shape...
. Since the condition is internal and usually asymptomatic, a person may not be aware of having a "double vagina." If necessary, the partition can be surgically corrected, however, there is no valid medical reason for such a procedure.
Diagnosis
Besides a physical examination, the physician will need imaging techniques to determine the character of the malformation: gynecologic ultrasonographyGynecologic ultrasonography
Gynecologic ultrasonography or Gynecologic sonography refers to the application of medical ultrasonography to the female pelvic organs, specifically the uterus, the ovaries, the Fallopian tubes, as well as the bladder, the adnexa, the Pouch of Douglas, and any findings in the pelvis of relevance...
, pelvic MRI, or hysterosalpingography
Hysterosalpingography
Hysterosalpingography is a radiologic procedure to investigate the shape of the uterine cavity and the shape and patency of the fallopian tubes. It entails the injection of a radio-opaque material into the cervical canal and usually fluoroscopy with image intensification...
. A hysterosalpingogram is not considered as useful due to the inability of the technique to evaluate the exterior contour of the uterus and distinguish between a bicornuate and septate uterus.
In addition, laparoscopy
Laparoscopy
Laparoscopy is an operation performed in the abdomen or pelvis through small incisions with the aid of a camera...
and/or hysteroscopy
Hysteroscopy
Hysteroscopy is the inspection of the uterine cavity by endoscopy with access through the cervix. It allows for the diagnosis of intrauterine pathology and serves as a method for surgical intervention .-Method:...
may be indicated.
In some patients the vagina
Vagina
The vagina is a fibromuscular tubular 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. Female insects and other invertebrates also have a vagina, which is the terminal part of the...
l development may be affected.
Treatment
Surgical intervention depends on the extent of the individual problem. With a didelphic uterus surgery is not usually recommended.A uterine septum can be resected in a simple out-patient procedure that combines laparoscopy and hysteroscopy. This procedure greatly decreases the rate of miscarriage for women with this anomaly.