Sebum levels during the first year of life.

Skin surface lipid levels in forty-five newborn babies and 193 infants aged less than 12 months were determined by an optical density method, using samples collected on ground glass. Although there was a wide individual range, sebum levels in the first week of life were very high, and were of the same magnitude as in adults. Females displayed a different pattern of sebum excretion from males. On the first day of life, the levels in females were lower than in the males but a large increase took place between the 3rd and 6th day, followed by a fall, bringing the level below that of the males. At 6 months the levels were low in both sexes. These findings suggest that there is a strong stimulation of sebum secretion before birth which probably stops at or soon after birth. Androgen may be involved in this stimulation and the probable role of dehydroepiandrosterone (DHEA) is discussed.