Insulin-like growth factors and their binding proteins are key regulators of fetal and maternal tissue growth and development during human pregnancy. Insulin-like growth factors, particularly IGF-II, are produced in abundance by the trophoblast cells of the placenta, whereas one of the insulin-like growth factor binding proteins, IGFBP-1, is the major secretory product of the maternal decidualized endometrium. This spatial (and temporal expression) of the insulin-like growth factor axis infers a sophisticated paracrine regulatory mechanism for controlling insulin-like growth factor function. This paper reviews the potential roles of IGFBP-1 in human pregnancy by examining its effects on growth, metabolism and migration at the maternal-fetal interface and how these might be influenced by autocrine-paracrine post-translational modifications.