Parents and caregivers can help children achieve their best possible health. The early years of life are crucial for health and physical, intellectual, and social/emotional development. If babies' physical needs are met regularly and consistently, they quickly learn that their caregiver is a source of satisfaction, creating a firm bond of trust and attachment. Healthy babies grow into healthy children and adolescents.
Colic refers to a specific pattern of excessive, intense crying and fussing that occurs without any apparent reason (for example, hunger, illness, or injury) in otherwise healthy infants. Colic typically begins within the first month of life, is worst when the infant is about 6 weeks of age, and ends, often rather suddenly, by 3 to 4 months of age.
Bacteria are microscopic, single-celled organisms. Only some bacteria cause disease in people. Other bacteria live inside the intestinal tract, genitourinary tract, or on the skin without causing harm. Some bacteria are even thought to help keep people healthy.
Children acquire many skills as they grow. Some skills, such as controlling urine and stool, depend mainly on the level of maturity of the child's nerves and brain. Others, such as behaving appropriately at home and in school, are the result of a complicated interaction between the child's physical and intellectual (cognitive) development, health, temperament, and relationships with parents, caregivers, and teachers (see also Childhood Development). Other behaviors, such as thumb sucking, develop when children look for ways to help themselves cope with stress. Still other behaviors develop in response to parenting style.
About one in 100 babies is born with a heart defect. Some are severe, but many are not. Defects may involve abnormal formation of the heart's walls or valves or of the blood vessels that enter or leave the heart.
Children’s bones grow continually and reshape (remodel) themselves extensively. Growth proceeds from a vulnerable part of the bone called the growth plate. In remodeling, old bone tissue is gradually replaced by new bone tissue. Many bone disorders come from the changes that occur in a growing child’s musculoskeletal system. These disorders may get better or worsen as the child grows. Other bone disorders may be inherited or occur in childhood for no known reason.
In the United States, the overall incidence of cancer in children and adolescents has increased over time. From 1975 to 2022, rates increased by approximately 0.8 per 100,000 each year. However, death rates decreased from 1970 through 2019 by 71% in children (from 6.3 to 1.8 per 100,000) and by 61% in adolescents (from 7.2 to 2.8 per 100,000).
Child maltreatment includes all types of abuse and neglect of a child under the age of 18 by a parent, caregiver, or another person in a custodial role (for example, clergy, coach, or teacher) that results in harm, potential for harm, or threat of harm to a child. Child neglect is the failure to meet a child’s basic physical and emotional needs. Child abuse is doing harmful things to a child.
Connective tissue is the tough, often fibrous tissue that binds the body's structures together and provides support and elasticity. Muscles, bones, cartilage, ligaments, and tendons are built mostly of connective tissue. Connective tissue is also present in other parts of the body, such as the skin and internal organs. The characteristics of connective tissue and the types of cells it contains vary, depending on where it is found in the body. Connective tissue is strong and thus able to support weight and tension.
Amblyopia, a common cause of vision loss in children, is a decrease in vision that occurs because the brain ignores the image received from an eye. Vision loss may be permanent if the disorder is not diagnosed and treated early in childhood.
Cholestasis is a reduction of bile formation or bile flow. As a result, bilirubin backs up into the bloodstream ( hyperbilirubinemia), leading to a yellow to yellow-green discoloration of the whites of the eyes and skin called jaundice.
Physical growth refers to an increase in body size (length or height and weight) and in the size of organs. From birth to about age 1 or 2 years, children grow rapidly. After this rapid infant and early toddler growth, growth slows until the adolescent growth spurt. As growth slows, children need fewer calories and parents may notice a decrease in appetite. Two-year-old children can have very erratic eating habits that sometimes make parents anxious. Some children may seem to eat virtually nothing yet continue to grow and thrive. Actually, they usually eat little one day and then make up for it by eating more the next day.
Human immunodeficiency virus (HIV) infection is a viral infection that progressively destroys certain white blood cells and makes people more vulnerable to other infections and some cancers and causes acquired immunodeficiency syndrome (AIDS).
Infections occur at all ages but are a great cause for concern in newborns because newborns, especially preterm ones, have an underdeveloped immune system and are more susceptible to infection. Although certain protective antibodies pass from the mother to the fetus through the placenta (the organ that provides nourishment to the fetus), the levels of antibodies in the fetus's blood may not be high enough to fight an infection.
Developmental disorders are better called neurodevelopmental disorders. Neurodevelopmental disorders are neurologically based conditions that can interfere with the acquisition, retention, or application of specific skills or sets of information. They may involve dysfunction in attention, memory, perception, language, problem-solving, or social interaction. These disorders may be mild and easily manageable with behavioral and educational interventions, or they may be more severe and affected children may require more support.
Apnea (not breathing) of prematurity is a pause in breathing that lasts for 20 seconds or more in an infant born before 37 weeks of gestation who is not known to have any underlying disorder that causes apnea.
Several important mental health disorders, such as depression, anxiety disorders, and eating disorders, often start during childhood and adolescence. Some disorders, such as autism, start only during childhood.
Few children make it through their first years without minor concerns. Crying, problems with feeding, rashes, and an occasional fever are common. These become health concerns only when they are extreme—for example, when children cry too much, when they are not growing well (see Failure to Thrive), or when they have high fevers that do not go away. Most childhood problems are not severe.
Muscular dystrophies are a group of inherited muscle disorders in which one or more genes needed for normal muscle structure and function are defective, leading to muscle weakness of varying severity. Muscle fibers appear deteriorated (dystrophic) when viewed under a microscope. Facioscapulohumeral dystrophy is the most common form of muscular dystrophy. Duchenne muscular dystrophy and Becker muscular dystrophy are the second most common forms. Duchenne muscular dystrophy is a more severe form. Becker muscular dystrophy is closely related to Duchenne dystrophy but starts later in a child's life and causes milder symptoms.
Neurofibromatosis is a group of genetic disorders in which many soft, fleshy growths of nerve tissue (neurofibromas) form under the skin and in other parts of the body, and flat spots that are the color of coffee with milk (café-au-lait spots) often develop on the skin.
Cerebral palsy refers to a group of conditions that involve difficulty moving and muscle stiffness (spasticity). It results from brain malformations that occur before birth as the brain is developing or from brain damage that occurs before, during, or shortly after birth.