A child is considered born prematurely when it comes before the 34th week of gestation.
The normal pregnancy lasts 40 weeks of gestation (fluctuates 37-42 weeks). Infants who are born before 37 weeks are premature and have an increased incidence of complications and a higher mortality, which are approximately proportional to the degree of prematurity. Infants who are born before 34 weeks are considered moderate born prematurely and those born between the 34th and 37th week of pregnancy are considered late born prematurely (late preterm). Infants who are born before 32 weeks’ gestation are considered very early birth and those who are born before 28 weeks of gestation are considered extremely early birth.
A child is considered born prematurely when it comes before the 34th week of gestation. The normal pregnancy lasts 40 weeks of gestation (fluctuates 37-42 weeks). Infants who are born before 37 weeks are premature and have an increased incidence of complications and a higher mortality, which are approximately proportional to the degree of prematurity. Infants who are born before 34 weeks are considered moderate born prematurely and those born between the 34th and 37th week of pregnancy are considered late born prematurely (late preterm). Infants who are born before 32 weeks’ gestation are considered very early birth and those who are born before 28 weeks of gestation are considered extremely early birth. The rate of premature births was 11.7% in 2011; 8.3% were late born prematurely and 3.4% were [born prematurely], including 2% who were very early born. Previously, all infants were <2.5 kg as early born. This definition is inappropriate, since many infants weighing <2.5 kg are ripe or even overripe, but just SGA (small for gestational age); they have a different appearance and other problems as premature babies. Children <2.5 kg are called children with low, those with <1.5 kg as children with very low birth weight (VLBW). Etiology The specific cause of preterm labor and premature birth, regardless of whether with or without premature rupture of membranes (Premature rupture (PROM)), is not known at present most patient. There are many known maternal risk factors, may be among those Socioeconomic factors Low socioeconomic status mothers with little formal education unmarried mothers cigarette smoking Obstetric history foregoing prematurity (risk factors for pregnancy complications: Preceding prematurity) foregoing multiple pregnancies foregoing multiple therapeutic abortion (induced abortion) and / or spontaneous miscarriage (spontaneous abortion) Current pregnancy-related factors pregnancy, which was achieved by in vitro fertilization (assisted reproductive techniques: in vitro fertilization (IVF)) Little or no prenatal care Poor nutrition during pregnancy (and possibly before)Untreated infections (eg. B. bacterial vaginosis [Bacterial vaginosis (BV)], Intraamniotische infection [formerly chorioamnionitis, intra-amniotic infection]) multiple pregnancy (for example, twins, triplets, risk factors for complications during pregnancy. Multiple pregnancy) cervical incompetence (formerly Gebärmutterhalsinkompetenz, cervical incompetence) Preeclampsia ( Pre-eclampsia and eclampsia) placental abruption (premature detachment of the placenta) However, most women who have premature babies, no known risk factors. Symptoms and complaints The premature child is small, usually weighing <2.5 kg, and has thin usually shiny pink skin through which the underlying veins are mostly good to see. There is little subcutaneous fat and hair, also the cartilage of the outer ear is not trained. Spontaneous activity and muscle tone are reduced, the extremities are not held in a flexed position, as is typical for a mature newborn. In boys, the scrotum may has only a few cross folds and the testicles are not deszendiert. In girls, the labia majora cover not the inner labia minora. The reflexes are developing at different times. The Moro reflex starts with 28 to 32 weeks of gestation and is fully developed with 37 weeks of pregnancy. The palmar reflex begins at 28 weeks and is fully developed 32 weeks. The tonic neck reflex starts at 35 weeks, and is about to see a month on the clearest after her due date. Complications Most complications are related to the immaturity of many organ systems. In some cases, complications dissolve completely, in others it is permanent dysfunction of the organs. Heart The most common cardiac complication Patent ductus arteriosus (PDA) The ductus arteriosus fails more likely kuzr after the birth of premature children. The incidence of PDA (Patent ductus arteriosus (PDA)) increases with increasing immaturity; PDA occurs <1750 g birth weight and about 80% <1000 g at nearly half of the infants. Approximately one third to one half of the infants with persistent ductus arteriosus have a heart failure in some form. Premature infants ? 29 weeks gestation who have respiratory distress syndrome at birth, have a 65-88% risk of symptomatic PDA. When infants are born after 30 weeks of pregnancy, the ductus closes at 98% by the time of discharge from the hospital spontan.ZNS Complications CNS Poor sucking and swallowing reflexes are apnea intraventricular hemorrhage development and / or cognitive delays Since children before 34 weeks have a poor coordination of sucking and swallowing reflex, they must iv or to be fed via a probe. The immaturity of the respiratory center in the brain stem leads to apnea (apnea of ??prematurity). but apnea can also alone caused by an obstruction in the area of ??the hypopharynx (obstructive apnea). Both forms together (mixed apnea) occur. The periventricular germinal matrix (a highly cellular accumulation of embryonic cells, overlying the caudate nucleus of the lateral wall of the lateral ventricles of the fetus) increases the risk of bleeding, which may extend into the ventricle (intraventricular hemorrhage, intracranial hemorrhage: Intraventricular and / or intraparenchymal hemorrhage). An infarction of the periventricular white matter (periventricular leukomalacia) can also occur for no apparent reason. Hypotension, inadequate or unstable cerebral perfusion and blood pressure tips (z. B. if crystalline or colloidal solutions are added rapidly i.v.) may contribute to cerebral infarction or hemorrhage. A violation of the periventricular white matter is a major risk factor for cerebral palsy and neurological delays. Premature infants, especially those with preceding sepsis (sepsis in neonates), necrotizing enterocolitis (necrotizing enterocolitis), hypoxia, and intraventricular or periventricular hemorrhage, the risk of development and cognitive delays are exposed. These infants require careful follow-up visits during the first year of life to identify auditory, visual and neurological delays. Particular attention must be focused on development milestones, muscle tone, Sprachkvermögen and growth (weight, length and head circumference). Infants with identified delays in vision should be referred to a pediatric ophthalmologist. Infants with auditory and neurological delays (including increased muscle tone and abnormal reflexes protection) early onset programs with physical, occupational and speech therapy should receive. Infants with severe neurological problems must werden.Augen may be referred to a pediatric neurologist Among the complications that affect the eyes, including retinopathy of prematurity (ROP) myopia and / or strabismus The retinal vascularization is completed shortly before the due date. Premature birth can disturb the normal Vaskularisationsprozess, which sometimes leads to abnormal development of blood vessels and visual impairment, including blindness (ROP, retinopathy of prematurity). The incidence of ROP is inversely proportional to the gestational age. The disease is usually between the 32th and 34th week of pregnancy. Myopia and strabismus (Strabismus) occur regardless of the ROP auf.Gastrointestinaltrakt frequent Complications Gastrointestinal include feeding intolerance with an increased risk of aspiration necrotizing enterocolitis A feeding intolerance is very common because premature babies a small stomach, immature sucking and swallowing reflexes and insufficient stomach -and intestinal motility have. These factors limit the ability of one, both oral and nasogastric (probe) to tolerate nutrition, and increases the risk of aspiration. Feeding intolerance decreases over time, especially when infants to be able to get some enteral nutrition. Necrotizing enterocolitis (necrotizing enterocolitis) manifests itself usually with bloody stool, food intolerance and a bloated, sensitive stomach. Necrotizing enterocolitis is the most common surgical emergency in premature infants. Complications in necrotizing enterocolitis of newborn babies include bowel perforation with pneumoperitoneum, intra-abdominal abscesses, Strikturbildungen, short bowel syndrome, septicemia and Tod.Infektion to infectious complications including sepsis, meningitis, sepsis (sepsis in newborns) or meningitis (acute bacterial meningitis in newborns) is at preterm infants about four times more common and occurs in almost 25% of VLBW infants on. The increased risk of infection is reduced to a central catheter, endotracheal tubes, skin lesions and a significantly decreased immunoglobulin levels in the serum. (Perinatal Physiology: Immunological function) .Nieren to renal complications include metabolic acidosis growth arrest Renal function is restricted, so that the control of concentration and dilution of urine is reduced. A relatively late-onset metabolic acidosis (metabolic acidosis), and failure to thrive may be due to the immature kidney is unable bound acids that accumulate through the diet with protein-rich food and bone growth, resign. There is a loss of Na and HCO3 bicarbonate over the Urin.Lunge The pulmonary complications include respiratory distress syndrome Bronchopulmonary dysplasia The formation of surfactant is often not sufficient to prevent the collapse of the alveoli and atelectasis, so that a respiratory distress syndrome arises (Idiopathic respiratory distress syndrome in newborns). Surfactant replacement therapy is used both for prevention and for the treatment of respiratory distress syndrome. Despite this treatment, many premature babies develop a chronic form of lung disease known as bronchopulmonary dysplasia (bronchopulmonary dysplasia (BPD)) is known. This requires a longer ventilator therapy and supplemental O2 therapy that goes beyond the 36th week. A palivizumab prophylaxis against respiratory syncytial virus is important for children with chronic lung disease ((infections with respiratory syncytial virus RSV) and human metapneumovirus: Prevention) .Metabolische problems to the metabolic complications include hypoglycemia hypoglycemia hyperbilirubinemia (neonatal hypoglycemia) and hyperglycemia ( neonatal hyperglycemia) are discussed elsewhere. Hyperbilirubinemia (neonatal hyperbilirubinemia) is more common in premature infants compared to term infants. Starting bilirubin levels of 10 mg / dL (170 mol / l) this may lead to a small kernicterus in sick premature infants. The higher bilirubin levels are due in part to the fact that the hepatic excretion mechanisms are not yet fully developed. This also includes a limited recording of bilirubin from serum, decreased hepatic conjugation to Bilirubindiglukuronid and reduced excretion into the bile ducts. Because of the reduced intestinal motility occur in the intestinal lumen by the enzyme ?-glucuronidase to increased deconjugating Bilirubindiglukuronid. This will unconjugated bilirubin increasingly reabsorbed (enterohepatic circulation of bilirubin). Conversely early meals enhance the motility of the gastrointestinal tract and thus reduce the re-absorption of bilirubin; characterized the incidence and severity of jaundice can in turn be reduced. In rare cases, a late cord clamping increases the risk of significant hyperbilirubinemia, as there may be in the child to an increased transfusion of red blood cells, which increased degradation of red blood cells results in hat.Temperaturregulation then The most common complication in temperature control hypothermia Premature babies have a very large body surface area in relation to body mass. Therefore, they lose heat rapidly and have difficulty to maintain their body temperature (hypothermia in newborns) upright when they are exposed to temperatures that are below the neutral thermal environment temperature. Diagnosis by new Ballard score estimated gestational Routine screening for complications of metabolism, CNS and eyes The findings on physical examination correlated with gestational age (assessment of gestational age-new Ballard score). Estimated date of birth and prenatal ultrasound, if made, determine gestational age. Initial tests investigate and meet the identified problems or problems, should also be carried out as routine evaluations. These include pulse oximetry, serum calcium and electrolytes, blood count, bilirubin, blood culture, alkaline phosphatase and phosphorus levels in the serum (to screen for prematurity osteopenia), hearing test, cranial ultrasonography. So information about cerebral hemorrhage and periventricular leukomalacia can be given. Also, check for retinopathy of prematurity by an ophthalmologist should be carried out. Weight, length and head circumference should be entered on an appropriate growth chart at weekly intervals. Follow-up investigation, if the initial laboratory tests were performed before the infant has taken full enteral feedings to him, some tests can be false-positive effect on metabolic disorders and should be repeated. In particular, positive screening tests of thyroid function and congenital adrenal hyperplasia (z. B. 17-hydroxyprogesterone) should be confirmed. Premature babies should be monitored for apnea and bradycardia, until they are 34.5 to 35 weeks (age adjusted) old. Before discharge from the hospital preterm infants should undergo a car seat test. By pulse oximetry is established that they can maintain good breathability and good O2 saturation when they are in the car seat. After discharge, premature babies should be dropped off for a thorough neurological follow-up investigation and provided with appropriate intervention programs for physical, occupational and speech therapy as needed. Prognosis The prognosis depends on the complications and its severity, but typically decrease mortality and complications with increasing gestational age and birth weight (survival and survival without severe impairment in infants with extremely low birth weight.). Survival and survival without severe impairment in infants with extremely low birth weight. Observed and maximum potential rate of survival (top) and survival without severe impairment (below) in infants with extremely low birth weight. (Adapted from Tyson JE, Parikh NA, Langer J, et al: Intensive care for extreme prematurity-moving beyond gestational age The New England Journal of Medicine 358:. 1672-81, 2008.) disability rates of single births vs. Multiple birth in preterm infants. The disability rate increases with increasing immaturity. For infants who were born before 25 weeks gestation, the disability rate for multiple births is higher than for single births (A) and under the multiple births, the disability rate for the second or subsequent birth is higher than for the first-born infant (B). (Adapted from Gnanendran L, Bajuk B, Oei J, et al: neurodevelopmental outcomes of preterm singletons, twins and higher-order gestations: a population-based cohort study Archives of Disease in Childhood-Fetal and Neonatal Edition 0. F1-F9 , 2014) therapy Supportive treatment Specific diseases and their treatments are discussed elsewhere in the MSD Manual. General supportive care premature babies get best in a neonatal intensive care unit or a special day-care center. Here is hiring the right temperature and the use of hydraulic incubators paramount. Careful hygiene, insbesodere before washing hands and after contact with patients is imperative. Infants need to be constantly monitored for apnea, bradycardia and hypoxemia, until they have reached a gestational age of 34.5 or 35 weeks. Parents should be encouraged to visit the child and to deal with it within the prescribed medical facilities. Skin-to-skin contact between mother and child (KMC) is beneficial to the health of infants and facilitates the maternal bond. It is also possible and safe when the infants are supported by fans and infusions. Premature babies should be brought before discharge from the Krankenhausin in the supine position as a sleeping position. Parents should be instructed to keep the children's beds free of fluffy materials such as blankets, quilts, pillows and stuffed animals with an increased risk of Sudden Infant Death Syndrome (SIDS, Sudden Infant Death Syndrome (SIDS)) related. Nutrition Nutrition is via a feeding tube until a sufficient coordination of sucking, swallowing and breathing is given. This is the case around the 34th week, so then breastfeeding is highly recommended. Most premature infants tolerate breast milk and thus be supplied with immunological factors and other important nutrients that are not contained in cow's milk (or infant formula from cow's milk). For children with very low birth weight (d. H. Children <1500 g) does not contain milk, however, enough calcium, phosphate and protein, and should therefore be amended accordingly. Alternatively, special infant formulas can be used for premature infants containing 70-85 kcal / 100 g (2.8-3.3 J / ml). If it is the first one to two days due to the condition of the child is not possible to supply a sufficient amount of fluid and calories orally or via a feeding tube, parenteral nutrition with protein, glucose and fats i.v. given to prevent dehydration and malnutrition. The feeding with mother's milk or a commercial premature infants by gavage can ensure the caloric intake of small sick premature infants satisfactory, v. a. including children with respiratory distress or apnea. First, small amounts (eg. As every 3-6 h 1-2 ml) are fed to stimulate the gastrointestinal tract. If this is tolerated, the amount and concentration of the meals be increased gradually over 7-10 days. At very low or critically ill children it may be necessary for a prolonged period of time to carry out a total parenteral nutrition through a peripheral or percutaneously or surgically created central venous catheter until the total amount of food is enteral tolerated. Prevention Although an early and adequate prenatal care is important as a whole there is no good evidence that such a pension or other interventions reduced the incidence of premature births. The use of Tocolytics to stop premature labor and to have the opportunity to administer antenatal corticosteroids to accelerate lung maturity is treated elsewhere (Preterm labor). Key points There are many risk factors for preterm birth, but they are not available in most cases. Complications include hypothermia, hypoglycemia, respiratory distress syndrome, apnea, intraventricular hemorrhage, developmental delay, sepsis, retinopathy of prematurity, hyperbilirubinemia, necrotizing enterocolitis and problems with feeding. Mortality and the likelihood of complications take with increasing gestational age and birth weight sharply. The findings are discussed and body temperature and feeding are supported. There is no evidence that prenatal care or other interventions reduce the incidence of premature births.