infant(redirected from Human baby)
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a child in the first year of life. At the moment of birth and the cutting of the umbilical cord, the child’s immediate tie with its mother’s body is broken off. and he enters the first period of his life, the neonatal period. The second period, that of infancy, begins with the child’s second month and continues until the end of his first year. During infancy there is intensive development of the functional capacities of all organs and systems in the body. The most characteristic feature of infancy is the increase in height and weight.
The body length of a full-term neonate averages 50 cm. Boys are usually somewhat larger than girls. During the first year of life the infant’s height increases by 25 cm. The height increase proceeds most intensively in the first quarter of the first year, when the monthly increase is 3 cm. In the second quarter the height increases by 2–2.5 cm a month: in the third, by 2 cm: and in the fourth, by 1.5 cm. The same general rule applies to weight: the younger the infant, the greater the rate of increase in weight. During the first month of life the infant’s weight increases by 600–700 g, and during the second by 800–1,000 g. In the first half year the average monthly increase in weight is 600 g. and in the second half it is 500 g. By the fifth or sixth month the infant’s weight doubles: by the end of the first year it triples.
The infant’s digestive organs are adapted to digesting the mother’s milk and only gradually acquire the capacity to assimilate other foods. For its high rate of metabolism and tissue growth, the infant’s body requires 2–2.5 times more food per kg of weight than an adult. The overload on the digestive organs is high, and as a result of the immaturity of the digestive tract, especially with improper nursing, it causes gastrointestinal upsets and metabolic disturbances. The quantity of saliva increases when the infant is 3.5–6 months old. The capacity of the neonate’s stomach averages 30–35 milliliters (ml): with each month it increases by 20–25 ml. By three months it is 100 ml. and by a year 250–350 ml.
The feces of a healthy infant are golden-yellow in color. (They turn green when exposed to the air.) With artificial feeding, the stool is lighter in color, sometimes with a slate-gray tinge, and it may have a putrid odor. In the first weeks of life, bowel evacuation occurs four or five times a day, later two or three times, and by the end of the first year once or twice a day (with artificial feeding, less frequently). Occasional belching up of small portions of milk is common to all children. Profuse vomiting after every meal usually occurs if the infant has swallowed large quantities of air while sucking. In such cases, it is sufficient to place the infant in an upright position for a few minutes after feeding and wait until he burps. Vomiting occurs when there is overeating; if it occurs an hour after feeding it indicates illness. Green stools with small white clumps may also occur with overeating, but the presence of other symptoms (frequent stools, watery feces with an admixture of mucus and blood, weight loss, vomiting, distended abdomen, or fever) are evidence of disease. The first teeth (milk teeth) appear in most healthy children in the sixth, seventh, or eighth month of life. By the end of the first year, the infant should have eight teeth. The cutting of teeth does not usually cause any diseases.
The infant’s respiratory organs carry an increased load, since his oxygen requirements are greater than those of an adult because of his high metabolic rate. The number of respirations per minute in an infant from the age of two weeks to six months is 40–45; at six and seven months, 35–40; and from seven to 12 months, 30–35. In an adult there are 16–20 respirations per minute. For this reason, the quantity of air passing through the lungs per unit time (rate of gas exchange) is also greater in an infant than in an adult. In the neonate there is an average of 2.5–3 pulse beats for each respiratory movement, and in a one-year-old the average is three or four pulse beats. The body temperature of children in the first year of life is 0.3°-0.4°C higher than that of adults.
Decreased excitability and easy fatigability of the cerebral cortex are characteristic of infants. The sense of taste is already developed in the neonate, and in the third month a healthy infant begins to differentiate quite well the principal gustatory stimuli. The precise differentiation of smells develops by the fourth month. The skin is very sensitive.
The circumference of the head, which in the neonate is 34–36 cm, increases especially rapidly during the first few months of life; by the end of one year it attains an average size of 46 cm. On the skull one may feel places where there are fontanels. The large fontanel closes, or grows over, by the end of the first year. The chest circumference in boys is usually larger than in girls. In neonates the chest is 2–4 cm less in circumference than the head, but by the end of a year it is larger, averaging 51 cm. The infant’s spine is very unstable, and if the child is too early transferred to a vertical position, made to sit, or carried in one arm, it is readily subject to curvature.
The normally developing, healthy infant begins to hold up his head in the second month. When lying on his stomach, he raises his chest and turns his head if he hears a sound. He responds to speech with a smile. By the third month his range of movements increases. The infant catches the direction of a sound, holds his head up well, turns over from his back to his side, and puts objects in his mouth. In the fourth month he takes and holds objects. turns from his back to his stomach, and lifts himself on his arms and leans on his palms while lying on his stomach. In the sixth month he can sit without support. turn from his stomach to his back, tries to crawl, and pronounces a few syllables such as “ba” and “ma.” In the seventh month he can rise to his knees hanging on to the bars of the crib, and he crawls. By the ninth or tenth month he can stand without support and walk with support; by one year he usually walks without support. At ten months he begins to pronounce simple words: “mama.” “baba.” “give,” and so forth. By one year he has command of eight to 12 words. The affectionate conversation of an adult with the child stimulates his speech development.
The infant’s growth and development proceed normally only with properly organized care and feeding and proper training. From the age of 1½ to three months he should be fed every 3½ hours, and after three months every four hours. Before the age of three months the infant consumes each day a quantity of food equal to half his weight; at the age of three to six months the amount of food eaten equals one-sixth his weight, and after seven months it equals one-seventh his weight. From the age of one month, the infant should receive natural juices (beginning with several drops, increasing to one teaspoon three times a day by three months, and 50 g a day by five months). At four months the infant is given raw pureed apple before his feeding (beginning with one-half teaspoon and gradually increasing to two teaspoons). From 4½ months the infant may be given one-quarter, and later one-half. a boiled, mashed egg yolk per day. At five months supplementary food such as vegetable puree or porridge is introduced. At seven months soup is introduced in the diet, along with three breast-feedings. At eight months pureed meat is given, with two breast-feedings. It is advisable to wean a healthy infant from the breast up to the age of 11 or 12 months (but not in the summer).
Care of the infant is based on the strictest observance of cleanliness in everything that touches him (the hands and clothing of caretakers, linen, clothing, toys, and dishes). His room should be wet-mopped. Each child should have his own bed. Optimal air temperature for an infant is 20°-22°C. The infant’s face and hands should be washed every morning with boiled water. The eyes are washed with boiled water or a boric acid solution (one teaspoon of boric acid in a glass of warm water) from the outer corner of the eye to the nose. The nose is cleaned with a cotton swab moistened with vaseline or boiled water. The outer ear is also cleaned when necessary with a cotton swab. The hands are washed separately. Fingernails and toenails are clipped when necessary with blunt-tipped scissors. The infant should be bathed daily in water of 36.5°-37°C. It is best to bathe an infant at 8 or 9 o’clock in the evening. For the prevention of intertrigo, the folds of skin are smeared with oil (vaseline or boiled vegetable oil) or powdered with baby powder. After each elimination the infant should be washed with warm water. If his hair becomes tangled at the back of his neck, it should be trimmed with a scissors. If dry, white flakes or scales appear on the infant’s head, the scalp should be smeared with boiled vegetable oil. These scales will fall off naturally during bathing.
In the first few months of his life the infant’s clothing consists of vests, jackets, and swaddling clothes. With daily laundering, he needs ten vests, six jackets, 24 diapers, 24 thin swaddling bands, and 12 fustian (flannel) ones. It is harmful to wrap the infant tightly and worse yet to swaddle him. Tight swaddling hinders proper development of his thorax, adequate ventilation of his lungs, and the development of his musculature. With tight swaddling the skin is susceptible to intertrigo and pustulate diseases. The infant should not be wrapped in oilcloth.
For children from two to nine months of age, the following routine is recommended: sleep, feeding, play, and then sleep again until the next feeding. The intervals between naps are increased gradually: a three-month infant may be awake without tiring for one or 1½ hours; a nine or ten month infant for 2½ hours, and a year-old or 1½ year-old for three or four hours. From the age of two months the infant is dressed in toddler pants for play.
It is necessary to develop the habits of independence and neatness in the infant early. By five months he should be able to hold a bottle, and by nine or ten months to take food from a spoon with his mouth and drink from a cup. At five or six months the infant should be set on the potty.
Outings are included in the infant’s regime regardless of his age. His clothing should be appropriate to the weather, so that chilling or overheating can be avoided. The infant is taken out for the first time in the cold season at the age of three or four weeks, if the air temperature is no lower than -5°C. For the first few days outings should last ten minutes; in the course of a week they are increased to 45–60 minutes. Two- or three-month-old infants are taken outdoors in winter at temperatures no lower than -10°C. On cold days it is best to have two 30-minute outings per day. One may take a three-to six-month-old infant on walks at temperatures of -12°C, and a one-year-old at -15°C. In winter there should be two outings per day with a total duration of one to three hours. For children who are used to sleeping outdoors in the summertime, this regime should also be maintained in the winter.
The tenderness and vulnerability of the mucous membranes of the respiratory and digestive organs cause frequent diseases of these organs. The infant’s body may exhibit an unusual reaction to mother’s milk, cow’s milk, citrus juices, strawberries, egg yolks, and other foods—this is called exudative catarrhal diathesis. In these children, redness of the cheeks and dry skin appear at the age of two to five months, accompanied by itching and sometimes peeling of the skin; there are scales on the scalp, and “geographic tongue” (alternation of smooth and rough areas) may be observed, as well as various rashes.
An infant two or three months old may develop rickets, especially in the winter. Rickets prophylaxis with vitamin D is started at the age of two weeks.
Children in the first two or three months of life are not susceptible to infectious diseases, because the transfer of antibodies during the embryonic period from the body of the mother immunizes them. In a few months this immunity disappears. Then, prophylactic inoculations are administered to the infant for prevention of infectious diseases: for tuberculosis, an intradermal injection of the vaccine BCG is given at the maternity home; for poliomyelitis, a vaccination is given at two months of age; a diphtheria-whooping cough-tetanus shot is administered at five months and again at six and seven months; and a smallpox vaccination is given at ten to 12 months of age. Influenza and other acute respiratory infections are especially dangerous to infants; at this age they are often complicated by pneumonia.
Proper physical training and strengthening of the infant’s body promote increased resistance to harmful environmental influences. At the end of the first month the infant should be placed on his stomach on a firm surface and massaged, at two months he should be exercised, and at two or three months air baths may be combined with the exercise. The duration of the air bath is two or three minutes at first and is gradually increased to 30 minutes for one-year-old children. From the age of six months, sponging with warm water (35°-36°C) with a moist mitten made of flannel or Turkish toweling is recommended. Every five to seven days the water temperature is lowered by 1°C. For one-year-old children the water may be 30°C. Sponging should last two to four minutes. After the sponging, the infant is rubbed dry until the skin is ruddy.
REFERENCESLeviant, S. M. Fizicheskoe razvitie detei pervykh trekh let zhizni.Leningrad, 1963.
Liublinskaia, A. A. Ocherki psikhicheskogo razvitiia rebenka,2nd ed. Moscow, 1965.
Razvitie i vospitanie rebenka ot rozhdeniia do trekh let. Edited by N. M. Shchelovanov. Moscow, 1965.
Arkhangel’skii, B. A., and G. N. Speranskii. Mat’ i ditia: Shkola molodoi materi.Moscow, 1956.
Spock, B. Rebenok i ukhod za nim,2nd ed. Moscow, 1971. (Translated from English.)
E. CH. NOVIKOVA