Late miscarriage is a spontaneous variant of termination of pregnancy at gestational age from 13 to 22 weeks. Depending on the stage, a woman experiences pain of a pulling or cramping type in the lower back and lower abdomen, bloody vaginal discharge is noted, the fetal egg or its fragments depart. For diagnosis, bimanual palpation, transabdominal gynecological ultrasound, analysis of HCG content are used. With a threatening late abortion, a protective regime, hormonal, antispasmodic, sedative drugs are prescribed. Emptying of the uterine cavity, antibacterial and antianemic therapy are indicated for patients with incipient and completed miscarriage.
Late spontaneous abortion (miscarriage) is observed in 2-4% of women with clinically confirmed pregnancy, which is about 1/5 of all cases of premature termination. The key difference between late miscarriage and premature birth is the non-viability of the fetus, which weighs up to 500 g during abortion and cannot develop independently outside the uterine cavity, which approximately corresponds to the 22nd week of gestation.
Unlike early spontaneous abortion, premature termination of pregnancy at 13-22 weeks in extremely rare cases is caused by genetic abnormalities. By this time, the main organs of the fetus have already been formed, therefore, miscarriage is usually caused:
- Cervical insufficiency. The failure of the cervix is caused by genetic abnormalities, hormonal disorders or mechanical damage in previous births. The omission of the fetal bladder and the opening of its membranes provokes the premature onset of labor. ICN is detected in 15-40% of patients with habitual miscarriage.
- Pathology of the uterus. The normal course of pregnancy is hindered by developmental anomalies (one-horned, two-horned, saddle-shaped uterus), inflammatory processes, adenomyosis, submucosal fibroids, other benign and malignant neoplasms.
- Pathology of the placenta and umbilical cord. Late miscarriage may occur due to delayed maturation or hypoplasia of the placenta, the presence of cysts and calcification sites in its tissues, inflammation and premature detachment. True nodes and thrombosis of the umbilical cord vessels also lead to fetal death.
- Immunological factors. Spontaneous late abortion may result from incompatibility of the blood of the mother and fetus according to the Rh factor or AB0 system.
In addition to the immediate causes leading to late abortion, there are a number of predisposing factors. Thus, pregnancy is more often spontaneously interrupted in patients with sexual infections, dishormonal conditions, concomitant somatic diseases (diabetes mellitus, arterial hypertension), gestosis. The risk of miscarriage increases in women who have previously undergone artificial abortions, gynecological operations, invasive diagnostic procedures and complicated labor with cervical damage. Late abortion can also provoke injuries, intoxication, infectious diseases, significant physical and psychological stress.
The mechanism of late spontaneous interruption of the gestational period is determined by the causes that caused it. At the same time, the tone of the uterus usually first increases and the contractile activity of the myometrium increases, which leads to shortening and opening of the cervix, rejection of the fetal egg from the uterine wall, followed by death and expulsion. Sometimes the death of the fetus precedes a late abortion. At the beginning of the second trimester, the shells during miscarriage are usually not opened, the fetal egg comes out completely. After the expulsion of all parts of the fetal egg is completed, the myometrium contracts, the bleeding stops.
Clinical manifestations depend on the stage of abortion. Patients with the threat of late miscarriage complain of the occurrence of pulling pains in the lower abdomen and lower back. Vaginal discharge is usually absent, less often spotting bloody. With the onset of a miscarriage, pain sensations increase, there are or increase secretions with an admixture of blood. At the stage of abortion, the uterine muscles contract regularly, which is subjectively perceived by the patient as cramping pain, abundant bloody discharge is observed, the fetal egg departs completely or partially. After the expulsion of the fetus, placenta and membranes, the pain disappears, the bleeding stops, for some time, scanty discharge may persist.
With a failed late miscarriage, there are no characteristic pains and spotting. In the expected period, there is no movement of the fetus, and if such movements were noted earlier, they stop. The patient notes the disappearance of subjective signs of a previously diagnosed pregnancy and softening of the mammary glands. 3-4 weeks after the death of the fetus, signs of general malaise may appear with weakness, dizziness, an increase in temperature to subfebrile figures. In some cases, it is during this period that the typical symptoms of miscarriage develop.
The delay in the uterine cavity of fetal elements, its membranes or placenta causes massive bleeding, leading to significant blood loss and can cause hypovolemic shock. Joining an inflammatory process to a miscarriage is manifested by the clinic of an infected abortion — a severe condition characterized by chills, fever, general malaise, bloody or pus-like discharge from the vagina, severe pain in the lower abdomen. Subsequently, such patients have an increased risk of developing inflammatory and dishormonal gynecological diseases. A long-term consequence of a late miscarriage is an increase in the likelihood of spontaneous termination of subsequent pregnancies. In addition, the stress experienced by a woman sometimes provokes the development of depression and psychological problems.
Late abortion can be suspected by the presence of typical clinical symptoms in women with a 13-22-week pregnancy. To confirm the diagnosis and determine the stage of miscarriage , the patient is prescribed:
- Bimanual palpation. With the threat of abortion, the size of the uterus corresponds to the gestational term, the tone of the myometrium is increased, the neck is normal in size, closed. At the beginning of miscarriage, bloody discharge enters through the slightly opened cervical canal. With a late abortion, an open external and internal pharynx is palpated in the course, a whole or fragmented fetal egg is revealed in the canal and/ or vagina. Upon completion of the expulsion of the fetus, the size of a well-contoured uterus is less than the previously established gestation period, the cervical canal is partially or completely closed.
- Transabdominal ultrasound. With a possible threat of miscarriage, an increase in uterine tone is determined. In cases when the fetus is alive, its heartbeat is recorded. The main echo signs of an abortion that has begun or a process in progress are hypertonicity of the myometrium, impaired placental circulation, opening of the internal uterine pharynx, rejection of the fetal egg. If the abortion turned out to be incomplete, fragments of the placenta and/or fetal egg are detected inside the uterus. A complete miscarriage is characterized by a closed uterine cavity.
- Determination of hormonal status. The study is particularly important for the choice of treatment tactics for the threat of miscarriage. To assess the level of hormones, the patient is prescribed a blood test for estrogens, progesterone, testosterone, a urine test for 17-ketosteroids. A decrease in the level of estrogens is indirectly indicated by an increase in the karyopycnotic index (KPI) of more than 10% during colpocytological examination.
The determination of the level of chorionic gonadotropin, which decreases in the event of fetal death, is highly informative. In case of a threatening miscarriage, an examination for intrauterine fetal infection (herpes, toxoplasmosis, rubella, cytomegalovirus), bacteriological smear examination, laboratory blood tests for sexual infections (PCR, ELISA), standard or advanced tests for chromosomal abnormalities, coagulogram can be additionally prescribed to identify its causes. Differential diagnosis of late miscarriage is carried out with ectropion, benign and malignant neoplasia of the genitals, cystic drift, acute surgical pathology. If necessary, an oncogynecologist, surgeon, and therapist are involved in the diagnosis.
Treatment of late miscarriage
Therapeutic tactics in spontaneous abortion depends on its form. If there is a threat of miscarriage, medication and a protective regime with the rejection of physical activity and sexual relations are recommended. The patient is prescribed:
- Hormonal drugs. The use of progestogens in combination with vitamin E is especially effective.
- Antispasmodics. Drugs can lower the tone of the myometrium and, accordingly, reduce pain.
- Methylxanthines. Medications of this group relax the myometrium, reduce the risk of thrombosis, improve blood circulation in the tissues of the uterus and placenta.
- Sedatives. To reduce the psychological stress experienced by a pregnant woman, magnesium preparations, a decoction of motherwort or valerian are used.
After eliminating the threat of late termination of pregnancy, the further management of the patient depends on what causes provoked this condition. If isthmic-cervical insufficiency is detected, stitches are applied to the cervix or a discharge obstetric pessary (Meyer’s ring) is installed in the vagina. The tactics of treatment of identified gynecological and concomitant diseases should take into account the specifics of prescribing various groups of drugs during pregnancy. The management of a pregnant woman in the diagnosis of intrauterine infection of the fetus or chromosomal aberrations is determined by the type of pathogen and genetic abnormalities.
Late incomplete abortion is a direct indication for emergency surgical care, which allows avoiding significant blood loss. In such cases, the remains of the fetal egg are removed with fingers, curette or vacuum aspirator. In parallel, an oxytocin dropper is prescribed. With a probable complete abortion at 13-16 weeks of pregnancy, ultrasound control and curettage of the uterus is recommended if decidual tissue and elements of the fetal egg are found in its cavity. If the miscarriage occurred at a later gestational period, and the uterus shrank well, you can do without curettage.
The tactics of managing a patient with a failed miscarriage and a dead fetus depends on the timing of pregnancy. Up to 16 weeks, the fetal egg is removed by instrumental methods, with a longer period, labor activity is medically stimulated. For this purpose, sodium chloride solution is administered intraamnially, antiprogestogens and prostaglandins are prescribed. After undergoing spontaneous abortion, antianemic and preventive antibacterial therapy is indicated. Patients with Rh-negative blood are recommended to administer antiresus immunoglobulin.
Prognosis and prevention
The prognosis for the fetus and the pregnant woman is determined by the reasons that provoked the late miscarriage. In the absence of developmental abnormalities and gross anatomical changes of the uterus, the timely appointment of a protective regime and drug treatment in most cases allows you to preserve pregnancy. When an abortion has begun, incomplete, complete and failed, it is impossible to preserve pregnancy, and the main efforts of obstetricians and gynecologists are aimed at helping a woman. After a miscarriage, the risk of repeated spontaneous abortion increases by 3-5%. For preventive purposes, women with a probable threat of termination of pregnancy are recommended to plan conception, preventative treatment of inflammatory diseases of the female genital area, timely registration and regular follow-up in a women’s clinic.