IGFBP3 and fetal growth restriction: Furthermore, IUGR animals showed a lower expression of Insulin-like growth factor (IGF) 1 receptor (Igf1r) both at 20 and 40 dpp, that together with the increased expression of IGF binding protein (Igfbp3) at 40 dpp pointed towards a downregulation of the IGF signaling within the ovary of IUGR rats.