Generality
The didelfus uterus is a congenital anomaly of the uterus.
Like the bicorne uterus and the uterus septum, it is included in the list of anomalies of the Müllerian ducts, pathologies with unknown causes that originate from a developmental error during embryonic life.
Figure: depiction of a didelfo uterus.
From the site: mulleriananomalies.blogspot.it
The presence of the didelphic uterus often causes unpleasant consequences during a pregnancy.
For a correct diagnosis, the pelvic exam is not enough. In fact, instrumental assessments are needed.
If women with a didelphic uterus do not experience any disorder associated with the abnormality, they should not undergo any treatment. Otherwise, doctors consider the possibility of surgical intervention.
Short reference to the uterus
Unequal and hollow, the uterus is the female genital organ that serves to receive the fertilized egg cell (that is, the future fetus) and to guarantee its correct development during the 9 months of pregnancy.
Figure: depiction of a normal uterus. According to the most accurate descriptions, the uterus presents two other areas, in addition to the body of the uterus and the uterine cervix: they are the isthmus of the uterus and the fundus (or base) of the uterus. The isthmus of the uterus is the narrowing that divides the body and the neck of the uterus. The fundus (or base of the uterus) is the upper portion of the body, located above the imaginary line that connects the two fallopian tubes. It is rounded in shape and protrudes forward.
It resides in the small pelvis, precisely between bladder (anteriorly), rectum (posteriorly), intestinal loops (superiorly) and vagina (inferiorly).
During the lifetime, the uterus changes its shape. If up to the prepubertal age it has an elongated appearance similar to a glove finger, in adulthood it looks a lot like an inverted (or upside down) pear, while in the post-menopausal phase it gradually reduces its volume and is crushed.
From a macroscopic point of view, doctors divide the uterus into two distinct main regions: a larger and larger portion, called the uterus body (or uterine body ), and a narrower portion, called the cervix (or cervix ). The uterine cervix protrudes, to a minimum extent, inside the vagina: it is the so-called "tench snout".
| Table. Measurements and weight of the uterus in an adult woman. | |
| Medium length | 7-8 centimeters |
Transverse diameter | 4-5 centimeters |
Antero-posterior diameter | 4 centimeters |
Weight | 60-70 grams |
What is the didelfo uterus?
The didelfus uterus, or double uterus, is a possible uterine malformation, characterized by the presence of two distinct uterine bodies, two separate cervices and, often, also two vaginas.
Despite the presence of two uterine bodies, the fallopian tubes are however two, one for each body.
The didelfus uterus is a congenital anomaly, that is, present since birth.
Causes
Despite the large number of research carried out, doctors and scientists have not yet been able to identify the causes of the didelphic uterus.
However, they managed to understand what the basic pathophysiological mechanism is.
PATHOPHYSIOLOGY
According to various studies carried out on the subject, the didelfus uterus derives from the incorrect development of the two paramesonephric ducts during embryogenesis (confirming the fact that the uterus didelphus is a congenital condition).
The paramesonephric ducts, or ducts of Müller, are small genital ducts, present in the embryo, which with stimulation by estrogens give rise to the uterus, the fallopian tubes and the vagina.
In other words, the paramesonephric ducts are the embryonic structures from which some of the main female genital organs are born.
In the case of the didelfus uterus, for reasons that are still unknown, the embryonic evolutionary process that the Müller ducts face is not successful; this generally has three effects:
- The formation of two separate uterine bodies
- The formation of two distinct cervical uterus
- The generation of two vaginas (compared to the two previous effects, it does not always happen).
Given the involvement of Müller's scholars, doctors and experts include the didelphic uterus among the so-called " Müllerian duct anomalies ". To be precise, the double uterus represents the class III Mullerian anomaly.
Also in the male embryo the paramesonephric ducts are present, however these regress around the 11th week of development, as they do not undergo the same estrogenic stimulations that occur in the female embryo.
NB: Readers who are part of the Müllerian duct anomalies are also reminded of uterine agenesis (class I), unicornus uterus (class II), bicornor uterus (class IV), septum uterus (class V), the arched uterus (class VI) and the T-shaped uterus (class VII).
Epidemiology
The didelfus uterus represents about 8% of the Müllerian duct anomalies and is a fairly rare condition. In fact, according to some statistical studies, it would affect a woman every 2000-3000 or so.
Please note: most likely, the didelfus uterus is underdiagnosed. Therefore, the numerical data concerning its frequency in the female population are not certain.
Sintom and consequences
To learn more: Symptoms Uterus Didelfo
In general, the didelfus uterus does not produce any particular symptoms in women who are carriers of it (to the point that many are even unaware of being so).
However, its presence often causes problems at the time of pregnancy.
These problems include:
- Spontaneous abortion (or involuntary termination of pregnancy) . According to certain statistical estimates, it is an event that affects about a third of women with a didelfo uterus.
- Preterm birth (or premature birth) . Doctors speak of premature birth when the birth takes place at least three weeks before the fortieth and last week of pregnancy.
The negative effects that a preterm birth can have on the unborn child depend on how long before the birth takes place. In other words, the more premature the childbirth is, the more serious are the health conditions in which the baby is born, when the mother gives birth to it. This is quite clear, given that the stay in the uterus serves the fetus to develop properly.
Depending on the moment in which it occurs, a premature birth can be defined as: late, if it occurs between the 34th and 37th week of gestation; severe, if it occurs between the 25th and 33rd week of pregnancy; extreme, if the child is born before the 25th.
According to some statistical studies, more than half of the pregnancies carried out by women with a didelfus uterus ends with a preterm birth.
From the pathophysiological point of view, the lack of adequate growth space is the cause of the early birth of the fetus. In fact, two distinct uterine bodies are insufficient, by capacity, to host a developing child.
- Bad position of the fetus . Some statistical research reports that the fetus takes a wrong position in just over 40% of pregnant women, carriers of the didelfus uterus.
The most common wrong positions are two: the breech and the cross (or transversal)
A child is in a breech position when he presents his feet instead of his head towards the exit; while it is in a sideways position when it faces one of the two shoulders towards the exit.
WHEN THE UTEROUS DIDELFO IS SYMPTOMATIC
In these situations, the manifestations consist of dysmenorrhea (severe menstrual pain) and dyspareunia (pain in the vagina or pelvis, during sexual intercourse).
ASSOCIATIONS
From the observation of numerous clinical cases, doctors and gynecologists have concluded that the didelfus uterus is often associated with some particular pathological conditions, including:
- Renal agenesis . It is the medical term that indicates the lack of one (unilateral) or both (bilateral) kidneys in the newborn.
- Transverse vaginal septum . It is a wall inside the vagina, which blocks its passage completely or partially. Its presence involves dyspareunia, additional difficulties during labor and cryptomenorrhea.
Cryptomenorrhea is the retention of the menstrual blood (therefore the blood does not come out as during normal menstruation), due to congenital obstacles located inside the vagina.
- Some skeletal defects . These disorders are very rare, however possible.
Complications of the didelfus uterus
- Infertility
- Endometriosis
- Unilateral haematocolus
- Unilateral hydrocolpo
Diagnosis
Doctors can identify the presence of a didelfus uterus by means of various diagnostic tests, including a sonohysterography (or hysterosonography ), a nuclear magnetic resonance, a hysterosalpingography and a hysterosonosalpingography .
sonohysterography
Sono-hysterography is a gynecological ultrasound that serves to visualize the uterine cavity from within; this examination is very useful for identifying uterine malformations, endometrial thickening, polyps and fibroids.
Like any ultrasound, it involves the use of an ultrasound probe, which the doctor leads into the uterus through the vagina (transvaginal way).
However, before this operation, the internal cavity of the uterus must be stretched (ie enlarged): to do this, the doctor injects (obviously into the uterus) a particular sterile physiological solution.
NUCLEAR MAGNETIC RESONANCE
Nuclear magnetic resonance (NMR) is a painless diagnostic test that allows the visualization of the internal structures of the human body without the use of harmful ionizing radiation (X-rays).
hysterosalpingography
Hysterosalpingography is a diagnostic procedure of the radiographic type, which involves the exposure of the patient to a (minimum) dose of X-rays. Through its execution, the doctor can evaluate the morphological aspect of the uterine cavity and the fallopian tubes.
For the visualization of the interested areas, a particular contrast liquid, opaque to X-rays, is needed, which an operator (or the doctor himself) injects specifically into the uterine cervix.
Hysterosalpingography is an examination that gynecologists prescribe to women with a suspected fertility problem, therefore its realization is less frequent than the two previous investigations.
It is one of the least invasive exams, since X-rays are ionizing radiation harmful to health.
Hysterosonograms
Hysterosonosalpingography has the same purposes as hysterosalpingography, but it is an ultrasound examination, just like the sonohysterography (with which it shares some procedural steps).
It is not invasive, because it involves the exposure of the patient to ultrasounds, which are not harmful to health.
Its execution is more frequent among women with a suspected fertility problem.
UTERO DIDELFO AND PELVICO EXAMINATION
If a pelvic exam reveals the presence of a double vagina and a double cervix, the gynecologist may suspect a didelfus uterus. However, to ascertain its actual presence, it needs more specific instrumental checks, such as those described above.
Moreover, not all cases of the didelfus uterus involve the presence of a double vagina or a double cervix.
Treatment
If the didelfus uterus is asymptomatic and does not hinder the possibility of having children, doctors do not resort to any particular treatment.
If instead it is responsible for a certain symptomatology or has caused problems in several previous pregnancies, they could consider the hypothesis of a surgical treatment. The planned intervention consists, in fact, in the union of the two uteri.
Moreover, if a transverse vaginal septum were present, the latter would also be eliminated.
TREATMENT IN THE PRESENCE OF A PRETERMINE HISTORY
When patients with a didelphic uterus have a history of preterm birth, doctors may opt for some solutions aimed at reducing the chances of an early birth.
One of these solutions is cervical cerclage, a surgical operation during which the operating surgeon applies, at the level of the cervix, a strip of synthetic tissue, which serves to strengthen the cervix and increase continence.
CAESAREAN SECTION
Most pregnant women with a didelfus uterus must undergo a caesarean section, regardless of whether the pregnancy ends or not.
Prognosis
According to experts, only 40% of pregnancies conducted by women with a didelfus uterus are successful, that is, they end with the birth of a healthy and alive child.
