Summary Puberty is a period in a life of a child when sex characteristics occur and growth velocity accelerates. According to adopted norms, the occurrence of signs of puberty before the age of 8 is regarded as precocious. This article focused on early pubertal development. as well as increased incidence of sexual precocity, in American girls and girls who had been adopted from developing countries into Western European countries. Environmental and individual conditions that influence normal and precocious puberty have been discussed. On analysis of professional literature, no alarming advancement in timing of puberty in Polish girls was ascertained. However, taking into consideration certain threats resulting from premature puberty (early initiation of sexual life, increased risk of sexually transmitted infections, early teenage pregnancies, breast cancer, obesity with all its consequences in adulthood), it is necessary to continuously monitor this occurrence, with special attention paid to the factors which may accelerate it.