A:

Polydactyly is a condition where a baby is born with an extra finger or toe. The more common ones are found on the little-finger side. And can come in different shapes and sizes, from a small extra piece of tissue to a fairly well formed digit. The extra finger or toe can be made of tissue and skin, with or without bone.

The smallest ones are usually just skin. And they can generally be removed easily before an infant leaves the nursery. Those that have bone or are more involved will need further evaluation before they can be removed.

Polydactyly is the second most common hand anomaly after syndactyly (joined fingers). These types of body appearances are usually caused by changes to a baby's genes. For example, as a baby is developing in the uterus, a gene may not form the right way, or may be missing or lost. This gene change may be inherited or in some cases caused by things in the environment.

Polydactyly may be the only physical difference you notice. Or it may be associated with other anomalies, syndromes or genetic diseases.

Talk with your baby's doctor. The baby’s medical history, family history and physical exam are all important factors used to determine the actual cause of polydactyly in an infant. Or if it is even necessary to pursue it at all.