sudden infant death syndrome (SIDS) or crib death, sudden, unexpected, and unexplained death of an apparently healthy infant under one year of age (usually between two weeks and eight months old). SIDS accounts for 10% of infant deaths and is the second highest cause of death (after accidents) in infancy. The risk is higher in males, in low-birth-weight infants, in lower socioeconomic levels, during cold months, and for babies who sleep face down.

Causal theories suggest that the infant may have immature or hypersensitive lungs, may have a defect in brain-stem control of breathing, or may be rebreathing carbon dioxide. Recent studies have shown persistent high levels of an infant form of hemoglobin in babies with known risk factors for the condition.

SIDS victims are thought to have brief episodes of apnea (breathing stoppage) before the fatal one. An alarm system that detects breathing abnormalities is sometimes used with infants suspected of being prone to SIDS. The American Academy of Pediatrics has recommended that babies be laid to sleep on their backs or sides.

infant respiratory distress syndrome (IRDS) or hyaline membrane disease, respiratory distress syndrome of newborns, most common in infants born prematurely or by cesarean section or having a diabetic mother. The immature lungs of such infants cannot retain air; the air spaces empty completely and collapse after the first (and each succeeding) exhalation. Plasma leaks out of the lung tissue and coats the air spaces with a pink coating that is glassy, or hyaline, in appearance, hence the alternate name of the disease. Exhaustion, resulting from the extreme effort required to breathe, has been responsible for the death of many afflicted infants.

IRDS is caused by a lack, in the immature lung, of a surfactant agent; the substance, a mixture of lipids and proteins, contributes to the elasticity of lung tissue and stabilizes air passages so that the lung remains partly aerated after each exhalation. Intensive care, including supplemental oxygen and, in the case of severe symptoms, aid in breathing from a ventilator, can often bring infants through the first five or six days, after which most recover completely. An artificial surfactant may be introduced into the lungs if a newborn is at high risk for IRDS. If labor begins prematurely and cannot be halted and tests show that the fetus's lungs are immature, steroids administered to the mother a few days prior to labor may promote lung maturation.

or crib death

Unexpected death of an apparently well infant. It occurs almost always during sleep at night and usually at 2–4 months of age. Sleeping facedown and exposure to cigarette smoke have been implicated. It is more common in cases of premature birth, low birth weight, and poor prenatal care. Many cases that would once have been labeled SIDS prove to be due to suffocation in bedding or overheating. Some babies who die of SIDS have been found to have brain stem abnormalities that interfere with their response to high levels of carbon dioxide in the blood.

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School or class intended for children age four to six as a prominent part of preschool education. The kindergarten originated in the early 19th century as an outgrowth of the ideas and practices of Robert Owen in Britain, Johann Heinrich Pestalozzi in Switzerland and his pupil Friedrich Froebel (who coined the term) in Germany, and Maria Montessori in Italy. Kindergartens generally stress the social and emotional growth of the child, encouraging self-understanding through play activities and creative expression.

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