Mongolian spots are seen most commonly over?

Ans. D. Presacral region. (Ref. Nelson Paediatrics 19th/Fig. 639-2).Mongolian spots, which are blue or slate-gray macular lesions, have variably defined margins; they occur most commonly in the presacral area but may be found over the posterior thighs, legs, back, and shoulders. They may be solitary or numerous and often involve large areas. More than 80% of black, Asian, and East Indian infants have these lesions, whereas the incidence in white infants is <10%. The peculiar hue of these macules is due to the dermal location of melanin- containing melanocytes (mid-dermal melanocytosis) that are presumably arrested in their migration from neural crest to epidermis. Mongolian spots usually fade during the first few years of life as a result of darkening of the overlying skin. Malignant degeneration does not occur. The characteristic appearance and congenital onset distinguish these spots from the bruises of child abuse. Although regarded as benign, recent data suggest that MS may be associated with inborn errors of metabolism and neurocristopathies. Mongolian spots usually resolve by early childhood and hence no treatment is generally needed if they are located in the sacral area. However, sometimes it may be required for extrasacral lesions for cosmesis.