A speech delay does not necessarily show up as mental retardation, but mental retardation may show up as a speech delay.
Delayed speech is caused by a variety of reasons such as a child’s ability to express himself or herself or a child’s ability to understand language at a level lower than normal for a child of his or her age. There are many common causes of language delay, such as hearing impairment, mental retardation, autism, central nervous system disorders, poor language environment, or diseases of the vocal organs.
Early intervention is needed for speech and language delays, or if the delay is due to a medical condition, then targeted treatment should be given. If the delay is caused by a physical disease, then targeted treatment should be provided. If the delay is caused by the language environment, hearing impairment, mental retardation, etc., then targeted training should be provided.
Parents are advised to consult a doctor as soon as possible for systematic evaluation and standardized treatment under the guidance of a professional doctor.