1, physiological jaundice. 2, “horse teeth” and “mantis mouth”: in the oral palate midline and gingival areas, there are yellow-white, rice-grain-sized particles, formed by the accumulation of epithelial cells or mucus gland secretions accumulation, commonly known as “horse teeth The yellowish-white, rice-grain-sized granules are formed by the accumulation of epithelial cells or mucus gland secretions, commonly known as “horse teeth”, which can naturally subside after a few weeks; there is a raised fat pad on each side of the cheek, which is useful for suckling. All are normal phenomena, not to pick through, so as not to occur infection. A small number of newborn babies have premature teeth in the lower incisors or other parts, called newborn teeth, which usually do not need to be removed. 3, breast enlargement and pseudomenstruation: newborns of both sexes 4-7 days after birth are resistant to breast enlargement, such as bean or walnut size, 2-3 weeks to subside, do not squeeze to avoid infection; some female babies 5-7 days after birth vaginal outflow of a little bloody discharge, or a large amount of non-purulent discharge, which can last for 1 week. All of the above phenomena are due to the interruption of estrogen from the mother. 4. Neonatal erythema and corn rash: 1-2 days after birth, polymorphic papules of different sizes often appear on the head, trunk and extremities, called “neonatal erythema”, which disappear naturally after 1-2 days. It can also form a yellowish-white rash on the tip of the nose, nose and face due to the accumulation of sebaceous glands, called “neonatal corn rash”, which disappears naturally after peeling off the skin.