The diagnosis of Down Syndrome is usually suspected after birth as a result of the baby's appearance. It is a particularly difficult time for the mother coupled with the natural stress of childbirth. Although there is no easy way to be informed, most families agree that being together with the baby and being told as soon as possible is the best way to proceed.

If Down Syndrome is suspected, a karyotype (gene analysis) will be performed to ascertain the diagnosis. There is a wide range of physical characteristics. Few children exhibit them all, and some only a few. Among the most common traits are:

	Muscle hypotonia or low muscle/floppiness
	Flat facial profile, a some-what depressed nasal bridge and a small nose
	An upward slant to the eyes - small eyes
	An abnormal shape of the ear - small ears
	A single deep crease across the center of the palm
	Hyper flexibility, an excessive ability to extend the joints
	Small skin folds on the inner corner and second toe
	Enlarged and protruding tongue in relation to the size of the mouth

The most consistent features in Down Syndrome are the facial appearance, the skeletal structure leading to short stature and the developmental anomalies of the heart.