Ovarian pregnancy is a gestational complication characterized by the attachment of the embryo to the tissues of the ovary. Most often it proceeds practically without subjective manifestations. The main complaints of patients include pelvic pain, spotting discharge from the genital tract, menstrual cycle disorders, menstruation delay, with rupture of the fetus – symptoms of “acute abdomen”, internal bleeding. Diagnostic measures include clinical examination, ultrasonography, analysis of serum chorionic gonadotropin levels. Treatment is mainly surgical, if necessary, blood loss is compensated.
O00.2 Ovarian pregnancy
Ovarian pregnancy refers to rare forms of ectopic pregnancy, it is registered somewhat more often than other variants of extra-tubal nidation. The proportion of this pathology is 0.15% among all gestations, and among gestations with ectopic embryo location – 0.1-3%. Ovarian localization of the embryo is registered in pregnant women of any age, there is no information on the prevalence of complications by age group due to the small number of cases. The growth of the fetal egg usually continues until the sixth to eighth week, the outcome is a rupture of the fecundity with the death of the embryo, although individual cases of progression of gestation to the terms of viability of the fetus have been described.
The etiology of ovarian pregnancy is still unknown. Of particular practical interest are the factors contributing to the development of pathology, however, there is no consensus here either. According to clinical studies conducted by a number of authors, in 90% of women, it is not possible to establish any cause of ovarian nidation and identify risk factors.
Other authors believe that the causes of ovarian embryo vaccination are similar to those in the most studied tubal pregnancy, including diseases (mainly inflammatory), surgical operations on pelvic organs, hormonal dysfunction, congenital malformations, underdevelopment of the reproductive apparatus. To date, the correlation of pathology with the following factors has been revealed:
- Method of contraception. Intrauterine contraception is considered the main risk factor. In women using this method, ovarian localization of the embryo occurs an order of magnitude more often than in the population. This may be due to the fact that these contraceptives reliably protect against implantation of blastocysts in the uterus, fallopian tubes, but they do not prevent ovarian nidation at all.
- Hormonal induction of ovulation. Clinicians consider the spread of assisted reproductive technologies to be one of the reasons for the increase in the number of cases of ovarian pregnancy. Currently, the connection of ectopic pregnancy with clomiphene has been established – the use of this drug significantly increases the likelihood of developing pathology. The risk increases with ovarian hyperstimulation syndrome.
- Ectopia of the endometrium. Ovarian endometriosis is considered one of the most significant predisposing conditions for gestational complications. Perhaps the more frequent development of ovarian pregnancy in women suffering from this disease is associated with increased tropicity of the fetal egg to endometrioid tissue. The cause may also be a spasm of the fallopian tubes due to hyperestrogenism against the background of endometriosis, which prevents the normal transit of the zygote.
The pathogenesis of ovarian pregnancy has not been studied to date. There are different hypotheses of the mechanism that prevents the movement of the zygote outside the ovary: thickening of the gonad protein membrane (inflammatory or other genesis), pathological acceleration of the development and differentiation of the trophoblast, due to which the implantation process begins ahead of time, dysfunction of the fallopian tubes (violation of peristalsis, capture of the zygote by fimbrial villi, spasm).
If the egg for some reason did not come out of the ruptured follicle, the sperm can penetrate into the ovarian cavity, where fertilization will occur, and then attachment to the follicular wall. If the egg is released from the Graaf bubble, but for some reason it did not get into the funnel of the tube, fertilization can occur directly in the abdominal cavity, after which the zygote is embedded in the folds of the mesothelium on the surface of the gonad.
There are other versions of blastocyst vaccination on the surface of the ovary. There is an assumption that most cases of superficial implantation are the result of a complete tubal abortion of a living embryo, and ovarian pregnancy is a consequence of its secondary implantation. Perhaps the surface implantation is due to the transmigration of the fertilized egg – its transition from the contralateral organ through the abdominal cavity. If by the time the gonad is reached, the blastocyst is ready for use, it can be implanted into the ovary.
Normally, the embryo attaches to the uterine mucosa, where conditions are provided both for its normal development and for protecting maternal tissues from destructive effects during placentogenesis. There are no such conditions in ectopic pregnancy. The growing egg stretches the already thin walls of the fecundity, and the invasion of the trophoblast, accompanied by the release of proteolytic enzymes, the germination of villi, aggravates the destruction, leading to rupture of the capsule, intra-abdominal bleeding of varying intensity.
There are different classifications of ectopic pregnancy depending on the criteria. Clinically, it is possible to distinguish a progressive and impaired (interrupted or interrupted) gestation variant with ovarian nidation. In addition, according to morphological characteristics, it is customary to distinguish two forms of ovarian pregnancy with clinical and prognostic differences:
- Epiovarial. This type is characterized by superficial implantation of the fetal egg. At the same time, the capsule of the fetus is thin, breaks in the early stages, without leading to massive bleeding, and the embryo resolves.
- Intrafollicular. Implantation and growth of the blastocyst occurs in the thickness of the ovary – inside the follicle. This form is more dangerous, since the rupture of the placenta is accompanied by severe pain syndrome, bleeding. The deeper the follicle is localized, the more extensive the blood loss.
Symptoms of ovarian pregnancy
Progressive ovarian gestation has no pathognomonic symptoms. Usually there are signs of normal pregnancy (changes in appetite, taste sensations), early toxicosis may occur (vomiting, hypersalivation, local or generalized itching). 90% of patients complain of vague, dull pulling or spastic pains in the lower abdomen, 80% – spotting spotting from the vagina, 63% – cycle disorders. A distinctive feature of the pathology is the absence of a delay in menstruation – 84% of pregnant women continue to menstruate, the rest of the delay is often insignificant.
Rupture of the placenta is marked by typical signs of internal bleeding, peritoneal shock – sudden severe pelvic pain radiating into the sacrum, hips, anus (with possible loose stools), accompanied by weakness, dizziness, nausea, vomiting, sweating, sometimes fainting. Significant blood loss, threatening with death, is indicated by the change of anxiety and anxiety by apathy, drowsiness, difficulty breathing, confusion.
The most threatening and frequent consequences of ovarian pregnancy are associated with massive bleeding. In case of untimely provision of medical care, irreversible multiple organ failure may develop. The consequence of hemoperitoneum is often pelvic adhesions – a source of chronic pain syndrome, secondary infertility. As a result of prolonged bleeding, Sheehan syndrome may develop in the future. Another negative outcome may be the loss of the ovary with its pronounced damage. A rare complication is the development of ectopic choriocarcinoma, a malignant tumor originating from trophoblast cells.
Diagnosis of ovarian pregnancy is carried out by an obstetrician-gynecologist. The doctor may suspect an ectopic pregnancy based on the analysis of the patient’s complaints, findings during a gynecological examination (cyanosis of the mucous membranes of the cervix and vagina, painful volumetric formation in the appendages, preservation of the pear-shaped uterus, its insufficient softening, size lag). The standard for the diagnosis of developing ectopic pregnancy in modern gynecology is the comparison of ultrasound data with the results of hormonal analysis.
- Ultrasonography. Transvaginal ultrasound allows to determine the topical localization of pregnancy, to differentiate ovarian pregnancy from other forms. Using modern equipment, using the technique of color Doppler mapping, the embryo in the ovary can be detected at the earliest possible time.
- Hormonal analysis. Allows you to establish the presence of an ectopically located pregnancy. A marker of egg growth outside the uterus is the level of b-units of chorionic gonadotropin in the blood. With normal gestation of short periods, there is an increase in b-hCG by two-thirds during every two days. If the embryo develops outside the uterus, this figure is less than half.
If the ultrasound is uninformative, MRI, uterine curettage, diagnostic laparoscopy are prescribed. Undisturbed ovarian pregnancy is differentiated with other forms of ectopic nidation, tumor and tumor–like formations of the ovary, salpingoophoritis, cystic drift, disturbed – with spontaneous abortion during uterine pregnancy, acute appendicitis, peritonitis. With acute pain, positive symptoms of irritation of the abdominal wall and other signs of intra-abdominal bleeding, the severity of blood loss and hemostatic disorders is assessed. To do this, a coagulogram, UAC is performed, diuresis, blood pressure, heart rate, pulse are measured.
Treatment of ovarian pregnancy
Treatment is carried out by an operating gynecologist. In case of acute intra-abdominal bleeding, the involvement of a resuscitator, a transfusiologist is required. Surgical treatment is traditionally accepted (partly due to the late diagnosis of pathology), but drug therapy is increasingly being used.
- Surgical intervention. Patients with impaired pregnancy, significant embryo size, and high b-hCG values need surgical treatment. Hemostasis is performed primarily. The scope of the operation depends on the duration of pregnancy, the degree of destructive changes, varies from embryo elimination to ovarian resection. Ovari- , adnexectomy has to be resorted to only in exceptional cases.
- Medical treatment. The conservative method is indicated for small fetal egg sizes in patients with undisturbed pregnancy, low levels of b-hCG. Drug treatment allows you to achieve good results, minimize the risk of adhesions. To delay the growth of the trophoblast, local injections of a cytostatic drug (methotrexate) are prescribed (into the cavity of the fetal egg).
- Replenishment of blood loss. Intensive therapy is carried out to patients in serious condition at the pre-hospital stage and continues in the operating unit, in parallel with the surgical operation. Infusion therapy (crystalloid solutions, plasma substitutes), the use of antifibrinolytics, vasopressors are indicated for the correction of hemodynamic and hemostatic disorders. In case of massive bleeding, hemotransfusion, autofusion is performed to replenish blood loss.
After surgery, rehabilitation treatment is carried out for two to six months in order to prevent the adhesive process and, as a result, infertility. In the early postoperative period, an artificial hydroperitoneum is applied, antibiotics are prescribed. Later, physiotherapy and massage are prescribed. During this period, pregnancy protection is necessary.
Prognosis and prevention
The outcome depends on the form of pathology, the period of diagnosis. The prognosis for the preservation of reproductive function is most favorable when establishing a diagnosis in the early stages, while pregnancy is not disrupted. After surgery for an interrupted ectopic pregnancy, 70-90% of women develop an adhesive process, every fifth has a pronounced one. Over the last quarter of a century, it has been possible to significantly reduce maternal mortality in ectopic pregnancy, now the mortality rate is 3-4 per 10,000 cases.
Since the risk factors of pathology are not clear, there are no clear developments regarding primary prevention. At the stage of pregnancy planning, intrauterine contraceptives should be abandoned in favor of barrier contraceptives, and measures should be taken to prevent tubal pregnancy: pre-pregnancy preparation with early diagnosis, treatment of diseases of the pelvic organs, correction of endocrine disorders. Secondary prevention includes early registration for pregnancy, anti-adhesive therapy after surgery.