一、引言:色素斑常見於骶和臀部,但偶然也有在背部和胸腹部,上下肢和頭頸部的,多數嬰兒祇有一塊,也有些多至十餘塊的。它的大小,有時小如菉豆,有時大如圓盤,形狀多為圓形,椭圓形,也有些是雜形和不規則形的。斑的邊緣多數清楚,也有很少數是??色澤由淡灰色到暗青色或暗黑色@種斑據Grimm,Schohl与Bahrawy等研究,在胚胎四個或五個月時,斑的色素細胞就開始出 First, the introduction: pigmented spots are common in the sacral and buttocks, but occasionally also in the back and chest and abdomen, upper and lower extremities and head and neck, most babies only one, and some as many as ten blocks. Its size, sometimes as small as green beans, sometimes as large as the disc, the shape of mostly round, oval, and some are miscellaneous and irregular shaped. Most of the spots on the edge of the spot are clear and few are found. The color varies from light gray to dark cyan or dark black. Species Grim, Schohl and Bahrawy et al., At four or five months in the embryo, Cells begin to come out