From Big Medical Encyclopedia

PREMATURE BIRTHS (partus praematurus) — childbirth at duration of gestation from the 28th to 38th week (37 full weeks). Items of river come to an end with the birth of the premature child with weight (weighing) from 1000 to 2500 g and 35 — 45 cm long, having signs of functional immaturity. Distinguish spontaneous and artificial premature births. If premature births repeat 2 — 3 times, then them call usual.

P.'s frequency of river, according to various researchers, fluctuates from 4 to 16% of total number of all childbirth. In obstetrical institutions of our country it does not exceed 6%.

Spontaneous premature births

their Reasons are very various. They can be caused by constitutional, alimentary, social, genetic and neuroendocrinal factors. In P.'s development by river also obstetric pathology matters — istmiko-cervical insufficiency (see), acute and hron, infections at the pregnant woman, a multiple pregnancy (see. Polycarpous pregnancy ), premature placental detachment (see) and placental presentation (see), toxicoses of pregnant women (see), fibromyoma of a uterus (see), adenomyosis of a uterus and other localizations of genital endometriosis (see).

According to S. G. Bebson, R. K. Ignatyeva, Shtukkensen, Kubinyi, Vavryk, one of the reasons of P. of river is traumatization of a neck of uterus during the previous artificial abortion (see. Abortion artificial ), what can result in inferiority of an internal uterine pharynx and development of istmiko-cervical insufficiency. The last sometimes develops owing to ruptures of a neck of uterus at the time of delivery. P.'s approach by the river is promoted by a surgical injury of a uterus at earlier made Cesarean section, plastic surgeries on a uterus or perforation of a uterus at abortion (see. Uterus ). The item of river at malformations of internal generative organs or infantility of a uterus (see. Infantility ) are a consequence patol. implantations of an oospore, insufficient vascularization of separate parts of a uterus, and also functional insufficiency of gonads. In the presence of endocrine diseases at the pregnant woman (a diabetes mellitus, a hypothyroidism, a thyrotoxicosis, dysfunction of adrenal glands etc.) rubles are P. a consequence of imperfect reorganization of the closed glands providing the normal course of pregnancy. The river can lead to P. patol, the course of pregnancy which is combined with toxicosis, a multiple pregnancy, the wrong provision of a fruit, anomalies of development or an implantation of placenta. Chromosomal anomalies of a fruit P.'s reason ruble happen seldom since in these cases pregnancy usually is interrupted in earlier terms.

Items of river proceed on type births in time (see): there is a patrimonial activity, there is a smoothing and expansion of a neck of uterus, izlity amniotic waters, the birth of a fruit and placenta. On a wedge, to a current the rubles menacing and begun P. distinguish. The rubles menacing to P. are characterized by increase in a tone and irregular sokratitelny activity of a metka. Clinically it is shown by pain in the bottom of a stomach and in a waist, and is frequent also insignificant bloody allocations from a genital tract, shortening and even disclosure of a neck of uterus sometimes to 4 cm. At inefficiency of therapy of the rubles menacing to P. the following wedge, a stage — the rubles who began P. who are characterized by emergence of more intensive colicy pains, smoothing and disclosure of a neck of uterus more than on 4 cm develops; in further P. rubles proceed as timely childbirth.

According to S. G. Bebson, A. I. Hazanova, etc., P.'s duration of river usually is more, than urgent, however at istmiko-cervical insufficiency shortening of the first period of childbirth is noted; premature gap fetal membranes (see) occurs approximately in 30 — 38% of cases. The third period of P. of river unlike the same period at timely childbirth is characterized by more frequent bleedings arising owing to hypotonia of a uterus or a delay of parts of a placenta (see. Hypotonic bleedings , Afterbirth period ). Due to the long current of P. of river and premature izlitiy amniotic waters (see. Premature bursting of waters ) frequency of puerperal septic diseases increases.

At to diagnosis The item of river should consider existence in the anamnesis of not wearing out, duration of gestation and existence of the specific, contributing to abortion factors. At objective inspection define the provision of a fruit and its estimated weight, intensity of patrimonial activity, extent of disclosure and smoothing of a neck of uterus, height of standing of the prelying part, a condition of a bag of waters. Apply sometimes such diagnostic methods as ultrasonic scanning (see. Ultrasonic diagnosis ), amnioskopiya (see), a tonusometriya, microscopic examination separated from a uterus for the purpose of identification of elements of a fruit (epithelial cells, lumps of syrovidny lubricant, a down, etc.).

Tactics treatments at P. the river depends on the period of childbirth, intensity of patrimonial activity, duration of gestation and viability of a fruit. Treatment is carried out in a hospital; it consists in braking of sokratitelny activity of a uterus and stimulation of maturing of pulmonary fabric of a fruit. Braking of sokratitelny activity of a uterus is shown in those cases of P. of river when duration of gestation does not exceed 37 weeks, the neck of uterus is opened less than on 4 cm, the estimated weight of a fruit does not reach 2500. It is contraindicated at death of a fruit, existence of anomalies of its development, at suspicion of an intrauterine infection, bleeding from patrimonial ways, the expressed toxicosis, and also at some somatopathies of the pregnant woman. Premature izlity amniotic waters (see) is only a relative contraindication for braking of patrimonial activity since careful overseeing of the pregnant woman at co-administration of antibacterial therapy creates conditions for extension of pregnancy and performing the therapy directed to maturing of pulmonary fabric of a fruit.

Apply R-adrenomime-tiki, inhibitors of prostaglandins to braking of patrimonial activity (pndometatsin), magnesium sulfate, spasmolytic, sedative and analgesic means. However at the choice of a method of treatment in all cases it is necessary to consider probability of an adverse effect of the applied therapy both on an organism of the woman, and on an organism of a fruit. In obstetric practice following R-adreno-mpmetiki most was widely adopted: brikanit, P re-Par (Ritodrinum), Partusistenum, alupent (me-toproterenolsulfat, on sulfate), berotek (Fenoterolum). These drugs are administered intravenously kapelno during 4 — 12 hours, further they are applied in tablets or candles. For stopping of side effect of adrenomimeti-k (tachycardia, nausea) appoint Isoptinum (verapamil) which is slowly entered intravenously (2 — 4 ml of 0,25% of solution) or orally on 40 mg by 3 — 4 times a day. It is possible to apply Indo-meta-tspn 50 — 100 mg in a dose in candles to suppression of a sokratitelny uterine activity, 2 times a day no more than 3 — 4 days, and also 25% solution of magnesium sulfate on 10 ml each 8 — 12 hours intravenously or intramusculary, for the purpose of reduction of adverse action by a fruit of medicines for prevention and treatment of the rubles menacing to P. it is necessary to use non-drug methods of braking of a sokratitelny uterine activity: an electrorelaxation, an electrophoresis using magnesium sulfate, acupuncture. At treatment of the rubles menacing to P. it is necessary to carry out prevention of a hypoxia of a fruit (see. Asphyxia of a fruit and newborn , Fruit ). Numerous the wedge, observations testify to expediency of use of glucocorticoids for the purpose of prevention of a syndrome of respiratory insufficiency at premature newborns (see. Distress syndrome ).

Stimulation of maturing of pulmonary fabric of a fruit is carried out by glyukokor-pkoida which promote maturing of the epithelium cosecreting surfactant (see). Glucocorticoids are shown in all cases of the rubles menacing and begun P. on condition of a possible delay of delivery for 48 — 72 hours before establishment of a maturity of a fruit of lu-subjects of a research of an amniotic fluid (see. Amniotic waters ). For the prevention of development of a syndrome of respiratory insufficiency in premature newborns a number of schemes is offered. differing on a dosage, duration and a way of administration of drug. Dexamethasone on 8 mg a day, during 2 days is most widely applied. The effect of influence of glucocorticoids depends on the duration of gestation and time which passed from the beginning of therapy before delivery. Short-term introduction of glucocorticoids of negative influence on a fruit and mother usually does not render.

Conducting premature birth depends on a condition of the woman in labor and a fruit, the obstetric anamnesis, the treatment which is carried out to time of pregnancy, an integrity of a bag of waters. In case of «immaturity» of a neck of uterus intramuscular injections of estrogen are shown. For acceleration of disclosure of a neck of uterus use of spasmolysants is recommended. At weakness of patrimonial activity vnut-trivenno enter oxytocin or prostaglandin of ¥2 and - However purpose of the means stimulating a sokratitelny uterine activity shall be careful (especially at a deep-premature fruit), careful control of a condition of a fruit is necessary. Frequent long pains can conduct to traumatization of a premature fruit. Opening of a bag of waters should not be sometimes made before disclosure of a neck of uterus on 6 cm of P. of river can be bystry or prompt therefore careful control of dynamics of patrimonial process is necessary. At bystry childbirth purpose of solution of magnesium sulfate or beta-adrenergic agonists is reasonable. For the prevention of an injury of a fruit it is reasonable to conduct the second period of childbirth at position of the woman in labor of a pas to a side. In all cases the river is shown to P. perineotomy (see) or hypodermic administration of solution of a lidaza to the area of a crotch. Avoid the operations injuring a fruit (an application of forceps, a vacuum ex-track - tion). It is not necessary to resort in the presence of a viable fruit to internal version (if necessary Cesarean section is shown). At pelvic presentation fruit (see) a manual grant it is necessary to render extremely carefully (more preferable to use a classical manual grant); Tsovyanov's method should be avoided since the injury of cervical department of a backbone of a fruit is possible. To the 34th Cesarean section is made not by of pregnancy according to obstetric indications from mother, after 34 not of Cesarean section can be made for the purpose of preservation of a fruit. At P. it is reasonable to river to exercise control of a condition of a fruit (a kardiotakhografiya, definition of acid-base equilibrium).

Throughout P. rubles conduct careful overseeing by a condition of the woman in labor: take temperature, the ABP, define quantity of leukocytes in blood etc. In case of threat of developing of an infection appoint antibacterial agents.

At P. of river use of an electroanalgesia is reasonable (see. Electroanesthesia ), nitrous oxides, a local and conduction anesthesia (see. Labour pain relief ). Good results at P.'s anesthesia by the river are yielded by a physiopsychoprophylaxis (see. Psychoprophylactic training of pregnant women ).

Forecast for mother depends on the weight of its state and the reasons which caused P. of river; the forecast for a fruit — from gestational age (see. Premature children ), complications during pregnancy and childbirth, from accession of an infection.

Prevention consists in identification. inspection and timely treatment of pregnant women which have a risk of early abortion (given birth to premature children, multigiving birth, with malformations of generative organs, neuroendocrinal disturbances etc.), the sparing abortion, timely and correct sewing up of ruptures of a neck of uterus after the delivery. After P. of river all women are subject to comprehensive inspection for the purpose of identification of their reasons and treatment.

Artificial premature births

Artificial premature births represent abortion by term from 28th before the 38th week. Rubles carry out artificial P. according to the following indications: from mother — heavy toxicoses of pregnant women, diseases of cardiovascular system in stages of a decompensation, malignant tumors, severe forms of a diabetes mellitus; from a fruit — its critical states (especially at the burdened obstetric anamnesis of the pregnant woman, existence at it of a diabetes mellitus, a Rhesus factor isoimmunization), congenital anomalies of a fruit, etc. The technique of calling of artificial P. of river does not differ from that at the full-term pregnancy (see. Childbirth ).

See also Nevynashivany pregnancies .

Bibliography: V. N. Nevynashivaniye's skinners and perenashivany pregnancies, Sverdlovsk, 1978; Kravets G. P. Comparative kliniko-gi-sterograficheskaya the characteristic of efficiency of complex treatment of the menacing premature births, in book: Antenatal protection of a fruit and prevention of perinatal pathology, under the editorship of. A. G. Papa., page 121, Kiev, 1979; M at the h and-e in G. S. and Frolov O. G. Health protection of a fruit and the newborn in the USSR, page 92, M., 1979; The Menacing premature births, under the editorship of Yu. I. Novikov and N. G. Koshelev, L., 1980; John son J. W. a. D p h i n N. H. Prévention of preterm labor, Clm-Obstet. Gynec., v. 23, p. 51, 1980; Morrison J. Page a. lake of Injection of corticosteroids into mother to prevent neonatal respiratory distress syndrome, Amer. J. Obstet. Gynec., v. 131, p. 358, 1978; Saling E. Möglichkeiten und Grenzen der Tokolyse, Arch. Gynäk., Bd 228, S. 67, 1979; Schutte M. F. a. o. The influence of betamethasone and orciprenaline on the incidence of respiratory distress syndrome in the newborn after preterm labor, Brit. J. Obstet. Gynec., v. 87, p. 127, 1980; Stamm-Scholer H. Tokolyse und Verhinderung der Frühgeburt, Pharmakotherapie, Bd 3, S. 12, 1980.

Century of M. Sadauskas, V. I. Chigreeva.