Hormone-containing cosmetics may cause signs of early sexual development

Exogenous hormone exposure can cause early sexual development, but only one report suggests that this may occur secondary to the use of hair-care products. This study evaluated the usage frequency and biological effects of hormone-containing hair-care products. We reviewed the records of 102 consecutive dependent children referred for evaluation of sexual precocity. Eight children (7.8%) were using these products. All eight were black (100%), compared to 57 (61%) of the 94 patients not using such products (p < 0.05). There was no significant difference between these two groups in mean age, sex distribution, height, height standard deviation score, bone age:chronologic age ratio, or serum estradiol level. We conclude that exposure to hormones in hair-care products may be more frequent than expected and should be considered in the differential diagnosis of early sexual development in children.