Developmental disabilities are a group of severe and long-term conditions due to physical, mental, or both physical and mental impairments. Physical impairments may include blindness and hearing loss while mental impairments may include learning and behavioral disabilities. It is also possible to have both physical and mental impairments such as in the case of Down syndrome. These conditions may begin anytime during the developmental period, which is from birth up to 18 years old which affects day-to-day living and functioning that usually last for a lifetime. In the United States, studies show that about one in six children has one or more types of developmental disabilities. Most developmental disabilities occur even before the baby is born while some can occur after birth which may be a result of infection or injury. Causes of developmental disabilities may include:
- Genetic or chromosome abnormalities.
- Parental health and behaviors during pregnancy which includes smoking and drinking alcohol.
- Complications during birth
- Infections during pregnancy
- Exposure of the mother and child to high levels of environmental toxins such as lead