Congenital velopharyngeal incompetence (VPI) is a condition in which the muscles and tissues of the soft palate do not close properly, resulting in a gap between the back of the throat and the nose. This gap can cause air to escape through the nose when speaking, resulting in a nasal-sounding voice.
The causes of VPI are not fully understood, but it is believed to be caused by a combination of genetic and environmental factors. Genetic factors may include a family history of VPI, certain syndromes, or chromosomal abnormalities. Environmental factors may include premature birth, low birth weight, or certain medical conditions.