Placental hyperplasia is an increase in the thickness and volume of placental tissue associated with the action of compensatory and pathological factors. There are no specific clinical symptoms. In the later stages, in the presence of placental insufficiency, the pathology is manifested by a change in fetal activity — an increase or slowdown in its movements. For diagnosis, ultrasound of the uterus, CTG, Dopplerography of placental blood flow, invasive prenatal research methods, laboratory tests are used. Treatment is aimed at improving blood flow in the utero-placental system, eliminating the cause of the disorder and correcting concomitant disorders.
In modern obstetrics, placental thickening is considered not as a separate nosological unit, but as an important diagnostic sign indicating the presence of another pathology. Normally, as pregnancy progresses, the placental tissue gradually thickens, reaching its maximum size by 34-36 weeks. After that, its growth stops, and the volume remains the same or even decreases somewhat. With placental hyperplasia, its mass reaches 750 g or more instead of the average 400-600 g, and the fruit-placental coefficient, reflecting the ratio of the weight of the child and placental tissue, by the end of pregnancy is no more than 2-3 instead of the normal 6-7.
Thickening of placental tissue is usually a consequence of compensatory reactions and protective mechanisms designed to ensure optimal conditions for the development and safety of the fetus. In some cases, an increase in the mass of the placenta is caused by pathological changes in its tissues. According to experts in the field of obstetrics and gynecology, the main causes of organ hyperplasia are:
- Hemolytic disease of the fetus. An enlarged placenta is one of the signs by which it is possible to suspect an isoserological incompatibility of the blood of the child and the mother. In case of immune conflict by Rh factor and blood group, true hyperplasia of placental tissue with angiomatosis of its villi contributes to sufficient oxygenation of the fetus.
- Severe anemia of the mother. With a decrease in hemoglobin levels to 70-80 or less g / l, compensatory mechanisms are activated aimed at improving blood supply to fetal tissues. The volume of placental tissue increases mainly due to the proliferation of vessels in chorionic villi, which allows to increase blood flow and improve oxygen supply to the baby.
- Severe diabetes of the mother. A feature of type I diabetes mellitus and gestational diabetes is the deterioration of microcirculation in various organs and tissues, including the placenta. Compensatory angiomatosis of chorionic villi, which leads to hyperplasia of the baby’s place, makes it possible to improve blood supply in the fetoplacental system, provide the fetus with oxygen and nutrients.
- Gestosis. Pathological vascular spasm, which forms the basis of such pregnancy complications, disrupts microcirculation, increases vascular permeability and fluid accumulation in interstitial tissue. Similar processes occur in the placenta – chorionic villi swell, which leads to false hyperplasia of the organ.
- Congenital malformations. Hyperplastic placenta provides normal oxygenation of the tissues of a child with congestive heart defects, cystic adenomatous lung defect, congenital teratoma, neuroblastoma, leukemia. Such defects occur with genetic abnormalities, intrauterine infection with rubella, cytomegalovirus, parvovirus B19, toxoplasmosis.
- Chronic endometritis. Inflammatory processes in the endometrium caused by pathogens of gonorrhea, syphilis, chlamydia, mycoplasmosis and other STDs can disrupt the normal formation of the placenta. An increase in the number of vessels in the villi, accompanied by true tissue hyperplasia, is a compensation for primary placental insufficiency.
- Acute infectious diseases of the mother. Placenta overgrowth in pregnant women who have had the flu, ARVI, and other infectious diseases is mainly protective. In such cases, an increase in the placenta is aimed at enhancing the immune effect. In addition, compensatory angiomatosis prevents possible microcirculation disorders.
- Multiple pregnancy. For the adequate development of two or more fetuses in the uterus, a larger amount of placental tissue is required. True compensatory hyperplasia of the child’s place in the case of carrying twins allows the developing fetuses to be supplied with sufficient oxygen and nutrients. With the underdevelopment of the placenta, the death of one of the children is possible.
- Diseases of the placenta. The mass of the placenta increases in the presence of volumetric formations in its structure — primary tumors (chorioangiomas, chorionteratomas) and purulent abscesses. Although placental neoplasia is usually small in size, their diameter sometimes reaches 5 cm or more. The baby’s place also thickens with inflammation of the fetal membranes (chorioamnionitis).
The mechanism of placental hyperplasia directly depends on the causes that provoked the thickening of the baby’s place. With a true proliferation of placental tissue, the pathogenesis is based on compensatory angiomatosis, which arose in response to oxygen starvation of the fetus. To improve fetoplacental blood supply, the number of vessels in the chorionic villi increases from 4-6 to 25-50 or more, which makes the placenta thicker. With false hyperplasia, the size and thickness of the child’s place change due to pathophysiological processes characteristic of the underlying disease. Usually in these cases, the volume of the organ increases due to interstitial edema, less often — fibrous and destructive changes. In some conditions, both mechanisms are activated — compensatory and pathological.
In the early stages of the disease, there are no clinical manifestations, thickening of the organ often becomes an accidental finding when conducting a planned ultrasound after the 20th week of pregnancy. As hyperplasia progresses, signs characteristic of placental insufficiency may occur — the fetus becomes more active, which is manifested by an increase and increase in its movements. A prognostically unfavorable symptom, with the appearance of which an urgent consultation of an obstetrician-gynecologist is required, is the fading of the child’s movements. A significant increase in the abdomen is noted only when hyperplasia is combined with polyhydramnios.
The consequences for the fetus and mother that occur in the presence of placental hyperplasia are associated with a possible violation of its main functions — nutritional, hormonal and protective. In the presence of pathological processes and destruction of placental tissue, fetoplacental insufficiency develops, resulting in a delay in intrauterine development, hypotrophy, hypoxia and in extreme cases, stillbirth. Pregnant women with an enlarged placenta have an increased risk of premature birth and the need for cesarean section. Violation of hormone secretion (estrogens, progesterone, chorionic gonadotropin, placental lactogenic hormone, relaxin) is fraught with weakness of labor activity, increased birth trauma, hypotonic bleeding in the postpartum period, hypogalactia.
The objectives of the diagnostic stage are to assess the degree of placental hyperplasia, to identify structural changes and signs of functional insufficiency, to clarify the causes that led to an increase in the organ. A comprehensive examination includes instrumental and laboratory methods to obtain accurate data on the condition of placental tissue, fetus and pregnant woman. For diagnostic purposes , the most valuable are:
- Transabdobinal ultrasound of the uterus. Sonography of an enlarged placenta shows its thickening in comparison with the normal limits for a specific period and the expansion of the interstitial spaces. The method is informative, starting from 18-20 weeks of gestation. Ultrasound also allows you to detect a violation of the structure of placental tissue, gross malformations, signs of hypotrophy of the child, polyhydramnios.
- Cardiotocography. The technique is of particular importance for detecting early symptoms of hypoxic conditions. With oxygen starvation of the child, a rapid muffled heartbeat is recorded. The subsequent increase in fetoplacental insufficiency is accompanied by a sharp decrease in the number of fetal heartbeats (less than 120 beats per minute).
- Dopplerography of uteroplacental blood flow. Due to the analysis of the blood velocity in the placental vessels, it is possible to timely identify violations of the transplacental dynamics caused by hyperplastic processes. The method does not determine the causes of the pathology, but allows an objective assessment of the functioning of the fetoplacental system.
- TORCH-complex. A comprehensive serological blood test is aimed at detecting infectious agents that affect the fetus in utero. With the help of analysis, infection with toxoplasmosis, herpes simplex, rubella, cytomegalovirus infection is confirmed. In the expanded version, the technique effectively diagnoses the carrier of not only the listed, but also other infections.
- Invasive prenatal diagnosis. If hyperplasia is suspected due to malformations, amnioscopy, amniocentesis, cordocentesis are used. Some of these methods also make it possible to simultaneously detect signs of hypoxia and inflammatory processes, assess the functional state and hemolytic status of a child in isoserological conflicts.
- Detection of genital infections. Since chronic inflammatory diseases in the pelvic organs can cause pathological processes in the placenta, pregnant women are prescribed PCR diagnostics, RIF, ELISA (RPR and other tests). In the presence of vaginal discharge, microscopy and bacteriological seeding with an antibioticogram are performed.
To assess the functional state of a woman’s body and identify extragenital pathology, general blood and urine tests, a biochemical blood test are prescribed, and glucose levels are determined. Fetometry and echocardiography are recommended as auxiliary methods of fetal examination. Differential diagnosis is carried out between diseases and pathological conditions that provoke thickening of the placenta. If necessary, the patient is consulted by an endocrinologist, dermatovenerologist, infectious disease specialist, urologist, geneticist.
The main goals of therapy are the elimination of the disease that caused hyperplastic disorders in the placenta, and normalization of uteroplacental blood supply. In addition to the use of medications, a woman is recommended to change her lifestyle: increase rest time and night sleep, eat well, avoid hypothermia, significant physical and emotional stress, and perform special exercises for pregnant women in a dosed manner. With a thickened placenta , the patient is prescribed:
- Etiological treatment. The choice of a specific method or scheme depends on the underlying pathology. In severe rhesus conflict, intraperitoneal hemotransfusion is used, in anemia — iron preparations with ascorbic acid, in infectious processes — antibiotics, in diabetes mellitus — hypoglycemic agents, etc.
- Drugs that normalize placental blood flow. To improve perfusion, actovegin, peripheral vasodilators, anticoagulants and antithrombotic drugs are used, which normalize blood microcirculation in the placenta, accelerate the processes of glucose and oxygen utilization, increasing resistance to hypoxia.
Additionally, vitamin and mineral complexes, immunocorrectors and essential phospholipids are included in the hyperplasia treatment regimen. Termination of pregnancy is performed only in severe cases of conflict due to Rh or AB0 factors, or when another pathology is detected that poses an immediate threat to the health and life of the pregnant woman or fetus.
Prognosis and prevention
The prognosis depends on the cause that caused placental hyperplasia, and in most cases, with adequate complex treatment, it is favorable. Prevention is aimed at early diagnosis of genital and extragenital pathology, possible malformations of the child. Pregnancy planning, timely registration in a women’s clinic, regular ultrasound screening, rehabilitation of foci of chronic infection, restriction of stay in crowded places in an epidemiologically unfavorable situation, taking iron preparations to prevent anemia are recommended.