Rubella in pregnancy is a viral infection transmitted by airborne droplets and provoking severe malformations in the fetus. The disease is accompanied by an increase in lymph nodes, hyperthermia, cough, conjunctivitis. 2-3 days after infection, rubella in pregnancy manifests itself as a papular rash, pathological elements initially appear on the face, then spread to the body, arms and legs. To diagnose the disease, serological tests are used to determine the immunological markers of IgM. There is no specific treatment, in the presence of severe fetal malformations, rubella in pregnancy is an indication for its termination.
General information
Rubella in pregnancy is a viral disease characterized by increased contagiousness. This disease is also known under the outdated names “German measles” and “rubella”. For the woman herself, pathology does not pose a particular threat, but in obstetrics it is considered to be a dangerous disease due to the high probability of embryo damage. Rubella in pregnancy is diagnosed infrequently. This disease mainly affects children, but about 20-30% of women of childbearing age remain susceptible to infection due to the lack of antibodies in the blood.
The danger of rubella in pregnancy also lies in the fact that it can occur not only in acute, but also in chronic form, without clinically manifesting itself in any way. In such a situation, there is no opportunity to identify risks to the fetus in a timely manner and decide on further tactics of pregnancy management, taking into account the presence or absence of congenital pathology of the baby. Rubella in pregnancy presents a different degree of threat depending on the period of embryogenesis. Infection in the first trimester, especially in the first weeks, in 80% of cases ends with malformations. In the second trimester, the risk of an unfavorable outcome is observed in 75% of babies, after 28 weeks the indicator decreases to 50%.
Causes
Rubella during pregnancy is caused by a pathogen of the genus togavirus, tropic to embryonic and lymphoid tissues. Infection occurs mainly by airborne droplets in close contact with the source of infection. The spread of viruses begins even in the incubation period, when there are no obvious signs of the disease, which does not exclude contacts with infected people. The contagiousness persists for 7 days before the appearance of the rash and for 1-2 weeks after its occurrence. Rubella during pregnancy can also be transmitted by household means when using common objects on which traces of biological fluids of an infected person have been preserved. It is proved that the pathogen is present not only in nasopharyngeal mucus, but also in blood, urine, feces.
Rubella during pregnancy is transmitted to the fetus through the vascular bed. Initially, the patagent penetrates into the lymph nodes of the mother, affects the tissues of the respiratory organs, after which it enters the blood, reaches the placenta and enters the baby’s body. Finally, the sequence of teratogenic effects of rubella during pregnancy has not been studied, but it has been proven that the pathogen provokes chromosomal changes, contributes to the disorder of mitotic activity of embryonic cells. Frequent hydrocephalus, slowing of mental and physical development with such a diagnosis are caused by inhibition and apoptosis of tissues, blood circulation disorder caused by the harmful effects of the virus.
Symptoms
Rubella in pregnancy, as well as outside of it, begins with an incubation period that lasts 11-24 days. Then a characteristic sign appears – an increase and soreness of the occipital, cervical and parotid lymph nodes. About a third of women suffer from joint pain caused by the penetration of the pathogen into the synovial fluid. After a few days since the onset of these symptoms, rubella during pregnancy manifests itself as a small pink papular rash. Elements can merge with each other. Initially, they are localized on the skin of the face, then spread to the body and limbs. Rashes disappear in the same sequence.
Rubella in pregnancy is often accompanied by signs of conjunctivitis: pain in the eyes, photophobia, lacrimation. Due to severe intoxication of the body, there is an increase in body temperature to 38-39C, weakness, fatigue, headache. Less often, patients are concerned about cough, sore throat, rhinorrhea, nasal congestion, redness of the mucous membrane of the pharynx. Rubella during pregnancy increases the risk of spontaneous abortion by about four times. Penetrating through the placental barrier, the virus reaches the fetus and provokes severe disorders of intrauterine development, which can be detected by ultrasound scanning. Additionally, the condition of the child and the concentration of the virus in the amniotic fluid in case of suspected rubella during pregnancy can be judged by amniocentesis data.
Rubella in pregnancy is accompanied by multiple embryopathies. On the part of the fetus, first of all, there is a characteristic Gregg triad. It includes such defects as deafness, blindness, heart failure. The development of cataracts is not excluded. Also, rubella during pregnancy causes a violation of the mental and physical development of the fetus, congenital dystrophy, cerebral palsy, idiopathic thrombocytopenic purpura. If a woman is affected in the late stages of gestation by the baby, such manifestations as vasculitis, a tendency to pneumonia with constant relapses, chronic exanthema are possible. In about a third of cases, rubella during pregnancy ends in a fatal outcome for the child.
Even if rubella in pregnancy did not provoke severe birth defects on the part of the fetus, which is typical for infections in the 2-3 trimester, it can have long-term consequences. In particular, the disease can give distant manifestations during puberty of a child and cause panencephalitis, insufficient production of growth hormone. Often, rubella suffered by the mother during pregnancy becomes the cause of an insulin-dependent form of diabetes mellitus in a child in adolescence. Hearing disorders, thyroiditis of autoimmune origin are also possible.
Diagnosis
Rubella in pregnancy is diagnosed by conducting specific serological tests indicating the presence of antibodies to the pathogen in the woman’s blood. If symptoms are detected or if the expectant mother is in the focus of infection, you should immediately contact an obstetrician-gynecologist and an infectious disease specialist to conduct a timely examination and assessment of risks to the health of the fetus. Rubella during pregnancy is more often detected using the enzyme immunoassay (ELISA), which shows the level of IgM. Antibodies to the pathogen begin to circulate in the patient’s blood 7 days after the introduction of the patagent into the body and remain there for 1-2 months.
Due to the high risk of rubella during pregnancy, PCR (polymer chain reaction method) is prescribed for the baby. Its purpose is to confirm the recent infection of a woman, to determine the RNA of the virus. As mentioned above, also if rubella is suspected during pregnancy, a blood ELISA is performed for IgG avidity to the pathogen. Infection is indicated by the presence of a high amount of IgM titer antibodies in the biological substance under study. They are the ones who talk about the acute course of the disease. In this case, it is necessary to establish the probable period of infection, assess the condition of the fetus (cordocentesis is mainly used) and determine the possibility of further management of pregnancy.
Treatment
Rubella during pregnancy, which occurred before 12 weeks, is an absolute indication for artificial termination, so it provokes the formation of severe malformations in the fetus. In case of infection at the period of 13-28 weeks of embryogenesis, a consultation is held, which decides whether there is a possibility of preserving pregnancy. If it is established that rubella during pregnancy did not harm the child’s health or the interruption was not carried out for any other reasons, the patient is injected with immunoglobulin in a dosage of 20-30 ml by intramuscular injection.
Specific treatment of rubella during pregnancy has not been developed. Patients are shown complete isolation in order to prevent the spread of infection and bed rest. If necessary, symptomatic therapy is prescribed. Rubella during pregnancy may require the administration of antipyretic drugs, antispasmodics, anti-inflammatory drugs. If a decision is made to continue carrying the fetus, the woman is placed in a high-risk group for the development of congenital anomalies of the baby. Additionally, treatment is used to prevent placental insufficiency, involving the use of medications to normalize blood flow. There are no peculiarities in the management of childbirth or the postpartum period in the case of rubella in pregnancy. The baby can be born both when passing through the natural birth canal, and by caesarean section.
Prognosis and prevention
When diagnosing rubella in pregnancy, the prognosis is extremely unfavorable. Infection in the first trimester in 80% of cases ends with the development of severe defects incompatible with life. With the continuation of gestation, stillbirth occurs in 20%. The same number of children born with a congenital form of the disease die in the first month of life. In 30% of women, rubella during pregnancy ends with spontaneous abortion. In 20% of cases of continued gestation, intrauterine stillbirth is noted. That is why such a diagnosis at the initial stages of gestation is an absolute indication for termination.
Specific prevention of rubella during pregnancy consists in the study of the serological status of a woman and vaccination according to individual indications 2-3 months before the planned conception. The same approach is used if the amount of anti-redness antibodies in the blood is below 15 IU/ml. To reduce the likelihood of developing rubella during pregnancy up to 16 weeks in case the patient enters the focus of infection, an immunoglobulin containing antibodies to the pathogen is administered. After conception, vaccination against rubella is contraindicated, although its accidental implementation is not a reason for artificial interruption. Nonspecific prevention of rubella during pregnancy involves the exclusion of contacts with possible carriers of infection and strengthening immunity.