The Mongolian spot: a study of ethnic differences and a literature review.

Four hundred thirty-seven consecutively born full-term neonates, delivered at Jackson Memorial Hospital, were examined for the presence of mongolian spots (MS). The spots were found in 96% of the Negro children, 46% of the Hispanic children, 9.5% of the Caucasian children, and in both of the Asian children in the series. The sacro-gluteal region was the most frequent site of pigmentation, with the shoulders next in frequency. Almost all the spots on the extremities were located on the extensor surfaces. The color was most frequently blue-green, but was also commonly greenish-blue, blue-gray, or brown. In a concurrent review of 124 newborn records, MS was not described by house officers in any, although the probability of its occurrence would have been approximately 90 cases, based on the results of the study. A comprehensive review of the history of the description of MS and theories of its development, as well as a review of the clinical aspects, is presented.