Incontinentia pigmenti is a genetic abnormality of the X-chromosome (sex chromosome) that causes death in male fetuses and abnormalities in female fetuses. There are three phases of skin abnormalities, as well as various malformations of the eyes, teeth and nervous system. The first skin abnormalities are not present at birth but appear within days after birth; the final dermatologic stage (an irregular, whorled pigmentation) develops a few months after birth. Teeth may be missing or cone-shaped, and there may be seizures, microcephaly (small brain), or disturbances of the motor system. Eye involvement occurs in approximately one-third of all cases. Abnormalities of the retina usually occur during infancy. If there is no evidence of eye abnormality within the first year, the prognosis for normal vision is good. Usually, one eye is involved and it is often abnormally small. The retina typically has nodular accumulations of cells containing melanin (pigment), which are covered by a proliferation of the outer layer of the retina. There are also changes in the vasculature (blood vessels) of the retina. Over time, both the skin and retinal abnormalities cease. There are some individuals, however, who develop delayed signs of the disease, and retinal changes may be seen as late as the age of eight years. Theories regarding the development and progression of incontinentia pigmenti are presented. (Consumer Summary produced by Reliance Medical Information, Inc.)