imaginary (chronological), or prolonged pregnancy.
True-term pregnancy lasts more than 10-14 days after the expected date of birth (290-294 days). A child is born with signs of over-ripeness, and his life is in danger. Usually in these cases there are changes in the placenta (petrifikaty, fatty degeneration, etc.).
Prolonged pregnancy lasts more than 294 days and ends with the birth of full-term, functionally mature child with no signs of over-ripeness and the danger to his life. The frequency of prolongation of 1,4-14%, an average of 8%.
Prolongation of pregnancy means the untimely (late) the emergence of labor, with its development are frequently observed violations of the uterine contractile activity, which leads to an increase in the number of surgical interventions, for intrauterine fetal suffering and increased perinatal mortality. In prolonged pregnancy is more correct to call timely delivery and at the true prolongation - belated birth overripe fruit.
Prolonged pregnancy - etiology and pathogenesis
Prolonged pregnancy accurately seen as a pathological phenomenon, due to certain reasons, depending on the condition of the body of both mother and fetus. Premorbid background for the prolongation of pregnancy may be a previously deferred childhood infectious diseases (scarlet fever, mumps, rubella, etc.), which play a significant role in shaping the female reproductive system, as well as extragenital disease.
Contribute to the prolongation of pregnancy infantilism transferred abortions, inflammatory diseases of internal organs. that cause changes in the neuro-muscular apparatus of the uterus and lead to endocrine disorders.
A role in the prolongation of pregnancy are endocrine diseases, disorders of fat metabolism, trauma, toxicosis of the second half of pregnancy. In primigravidas (especially older) perenashivanie occurs more frequently than multiparous.
Has a meaning and a hereditary factor. The main pathogenetic moments leading to the prolongation of pregnancy are functional changes in the central nervous system, autonomic and endocrine disorders. A large role is played by making breach of estrogens, progestogens. corticosteroids, oxytocin, some tissue hormones (acetylcholine, catecholamines, serotonin, kinins, histamine, prostaglandins), enzymes and vitamins zlektrolitov.
Has a definite value as the state of the placenta and fetus. Abnormalities in fetoplacental system is one of the reasons for the late emergence of labor and its abnormalities. Overripe fruit of his need for oxygen increases, decreases the stability of the central nervous system to oxygen deficiency, the same time, there are profound changes in the placenta (degeneration, calcification, the dissociation of maturation). With prolongation of pregnancy, the need for oxygen in the fetus increases, and resistance to hypoxia is reduced, resulting in the placenta to the fetus changes make it difficult to deliver the required amount of oxygen and other necessary substances. This creates a vicious circle of pathological processes characteristic of post-term pregnancy.
Prolonged pregnancy - clinical
The clinical picture of post-term pregnancy is expressed softly, diagnosis is difficult. In true prolongation of pregnancy over 41 weeks is often observed, the lack of increase in body weight of pregnant or reduced by more than 1 kg decrease in abdominal circumference at 5 - 10 cm, which is usually associated with a decrease in the amount of amniotic fluid, decreased skin turgor, less than the fall in body weight due to secondary post-term fetus hypotrophy, oligohydramnios and green staining of amniotic fluid, a high standing of the uterus, the selection of milk, not colostrum, strengthening or weakening of the fetal movements, which indicates that fetal hypoxia due to violations of the utero-placental blood flow, changes in frequency. rhythm and timbre of fetal heart tones, immaturity or lack of maturity of the cervix, the large size of the fetus. increased density of cranial bones, sutures and fontanelles narrow.
During labor at term pregnancy is characterized by numerous complications, premature or early rupture of membranes, anomaly of labor activity, prolonged delivery, fetal hypoxia and birth trauma. As a rule, intrauterine fetal hypoxia manifested by prolongation of the start of labor or after preterm rupture of membranes, which is associated with worsening utero-placental blood flow due to the functional and morphological changes in the placenta. Hypoxia contribute to the reduced function of the adrenal glands of fetal sensitivity to oxygen deficiency during birth due to increased maturity of the central nervous system, reducing the ability of the head to the configuration, large size fruit. frequent violations of uterine activity, arousal or stimulation of labor, frequent surgical interventions during childbirth.
Prolonged pregnancy - Diagnosis
The diagnosis of prolonged pregnancy is usually made on the basis of history and data from clinical, laboratory and instrumental methods of investigation. It is necessary to assess the overall condition of the pregnant woman, during the pregnancy (toxicosis), set the period of occurrence of menarche, menstrual cycle characteristics, the presence of infantilism, endocrine diseases, inflammatory diseases transferred sexual organs, abortion, the prolongation of pregnancy in history.