Children born after assisted reproduction tecniques are exposed to high doses of hormones in the intrauterine period. The long-term health status of children exposed to high doses of hormones especially during early prenatal development is not known. However, it is discussed that these children may have a risk for low birth weight, prematurity, high blood pressure and high blood glucose and precocious puberty. Here, five subjects who were born with low birth weight using assisted reproduction techniques and who were diagnosed as premature puberty are presented to draw attention to the relation between prenatal exposure to hormones and precocious puberty. (Turk Arch Ped 2012; 47: 213-5)