Leptin in pregnancy

Leptin is a polypeptide hormone that aids in the regulation of body weight and energy homeostasis and is linked to a variety of reproductive processes in both animals and humans. Thus, leptin may help regulate ovarian develop ment and steroidogenesis and serve as either a primary signal initiating pu berty or as a permissive regulator of sexual maturation. Perhaps significan tly, peripheral leptin concentrations, adjusted for adiposity, are dramatic ally higher in females than in males throughout life. During primate pregna ncy, maternal levels that arise from adipose stores and perhaps the placent a increase with advancing gestational age. Proposed physiological roles for leptin in pregnancy include the regulation of conceptus growth and develop ment, fetal/placental angiogenesis, embryonic hematopoiesis, and hormone bi osynthesis within the maternal-fetoplacental unit The specific localization of both leptin and its receptor in the syncytiotrophoblast implies autocri ne and/or paracrine relationships in this endocrinologically active tissue. Interactions of leptin with mechanisms regulating pre-eclampsia and matern al diabetes have also been suggested. Collectively, therefore, reports sugg est that a better understanding of the regulation of leptin and its role(s) throughout gestation may eventually impact those causes of human perinatal morbidity and mortality that are exacerbated by intrauterine growth retard ation, macrosomia, placental insufficiency, or prematurity.