Septate uterus is an anomaly of intrauterine development characterized by the presence in the uterus of two halves (hemipoles) separated by a septum. The presence may be manifested by algodismenorrhea, uterine bleeding, infertility or miscarriage. Septate uterus diagnosed during ultrasound, ultrasound hysterosalpingoscopy, hysteroscopy, MRI or spiral CT, laparoscopy. Treatment of this defect is reduced to transcervical excision of the septum through a hysteroscope. After excision of septate uterus, the chances of pregnancy and natural childbirth increase significantly.
Septate uterus occurs in 2-3% of women in the general population and is one of the most common malformations of the female reproductive system (48-55%). Disease can have different lengths, and therefore there is an incomplete and complete septate uterus reaching the cervical canal. A longitudinal septate uterus from 1 to 6 cm long is more common, and a transverse septum is less common. The presence of septate uterus is usually detected relatively late when examining patients for menstrual dysfunction, habitual miscarriage or infertility. This disease in some patients is combined with kidney abnormalities.
In the intrauterine period, the uterus develops as a result of the fusion of paramesonephral (Muller) ducts. Normally, by 19-20 weeks of gestation, the sewerage and resorption of the median septum separating the uterine-vaginal canals and the formation of a single cavity in the uterus are completed. If organogenesis is disrupted under any adverse factors, this leads to the preservation of the median septum in the uterine cavity.
Hereditary causes, early or late pregnancy toxicosis, placental pathology, maternal infections (rubella, measles, toxoplasmosis, etc.), diabetes mellitus, bad habits, poor nutrition, ionizing radiation, drug exposure, etc. play a role in the etiology of the development of septate uterus in the fetus.
Patients often have menstrual cycle disorders such as menstrual cramps or pathological uterine bleeding. Other manifestations are habitual miscarriages (spontaneous termination of pregnancy), less often infertility. The risks of spontaneous abortion in patients with septate uterus in the first trimester of pregnancy are 30-60%, in the second — about 5%.
When an embryo is implanted to an intravascular septate uterus, its development is disrupted, which leads to miscarriage. In addition, the presence of septate uterus reduces the volume of the uterine cavity and prevents the growth of the fetus during pregnancy. Often, disease is combined with isthmic-cervical insufficiency, which causes termination of pregnancy in the second trimester. Also, the presence of this disease can provoke an incorrect transverse position of the fetus, premature birth, poor contractility of the uterus during childbirth. In patients with septate uterus, there is a decrease in the ability to conceive.
According to statistical data collected by clinical gynecology, the presence of septate uterus is more often detected during examination for habitual infertility, miscarriage of pregnancy or with separate diagnostic curettage. During ultrasound of the pelvis, disease is not always determined. Sometimes the partition is visualized as a thin-walled structure running in the anteroposterior direction. According to ultrasound data, it can be difficult to distinguish from a two-horned uterus.
Ultrasound hysterosalpingoscopy is more informative in the diagnosis of this anomaly, during which it is possible to identify septate uterus, its length and thickness. To exclude abnormalities in the development of the urinary system, kidney ultrasound is indicated. From endoscopic studies, hysteroscopy and laparoscopy are used in the diagnosis. Laparoscopy may reveal an enlarged uterus in diameter, the presence of a whitish stripe or a slight retraction in the sagittal direction, or asymmetry of the halves of the uterus.
Hysteroscopy serves to clarify the type of defect and its surgical elimination. During hysteroscopy, the gynecologist sees a triangular strip of tissue of various lengths and thicknesses dividing the inner space of the uterus into two isolated hemipoles, from each of which the mouth of the fallopian tube departs. If it is impossible to differentiate the type of intrauterine anomaly, MRI or multispiral CT is resorted to. The possibilities of hysterosalpingography in the diagnosis of septate uterus are about 50%.
When disease is detected, metroplasty is performed, the purpose of which is to create a single uterine cavity. Most often, surgical dissection is performed by transcervical access through the hysteroscope channel in the transverse or longitudinal direction. Endoscopic scissors are used to dissect a thin and narrow septum; a hysteroresectoscope is used to eliminate a wide, thick, vascularized septate uterus. Laser reconstruction of the uterine cavity is possible during surgical hysteroscopy.
With a complete septate uterus reaching the cervical canal, it is customary to preserve the cervical part of the septum in order to avoid the development of secondary isthmic-cervical insufficiency. As a result of metroplasty, the symmetrically located mouths of the fallopian tubes are revealed during visual inspection. Simultaneous surgical hysteroscopy and laparoscopy is justified, which allows to control the depth of dissection of uterine tissues. After the elimination, estrogens are prescribed or an IUD is installed to accelerate epithelialization and reduce the risk of formation of intrauterine synechiae.
Transcervical hysteroscopic excision is the most gentle and low-traumatic method that does not leave scars. The risks of miscarriage in operated patients decrease, the frequency of normal childbirth increases to 70-85%. While maintaining problems with fetal gestation, a woman can become a mother with the help of ART, namely surrogate motherhood. In vitro fertilization of the patient’s egg can be carried out using the husband’s sperm or donor sperm, after which the embryos are transplanted into the uterus of the surrogate mother.
Hysteroscopic dissection may be complicated by perforation of the uterus. Since hysteroscopic resection of the septum is accompanied by thinning of the uterine fundus, there are risks of rupture of the uterus during pregnancy. The management of pregnancy in patients after excision requires increased attention and control by an obstetrician-gynecologist.