The patient may have growth retardation and though as a baby may be normal size, will not grow as tall. Average height for an adult male with Down syndrome is 5 ft 1 in and for a female it is 4 ft 9 in. Bow leggedness is common. Obesity occurs with aging.
There is decreased mental function and the IQ may range from mild disability (50 to 70) to moderate (35 to 50). There can be language development delay both from hearing impairment and speech delay.
Gross motor skills like crawling and walking can be slow to mature and fine motor skills may take time to develop.