Cardiovascular Neuroendocrinology of Pregnancy

Neuroendocrine hormones are released primarily from the anterior and posterior pituitary, under the influence of hypothalamic input, to maintain physiological processes related to growth, metabolism, fluid homeostasis, and sexual development. During pregnancy, the placenta is integrated into the complex feedback systems among the hypothalamus, pituitary, and its target organs and contributes to the maintenance of a supportive maternal–fetal environment. Many adaptations associated with gestation are cardiovascular in nature and mediated by pituitary and placenta-derived factors. Of these, predominant changes include an altered threshold for vasopressin release, which supports increased plasma volume, and elevated prolactin levels to promote lactotroph development, angiogenesis, osmoregulation, and immune function. Other defining features include increased total thyroid hormones, the replacement of growth hormone by placental growth hormone, and local placental production of adrenal-cortex stimulating hormones. The neuroendocrine axis is a major regulator of maternal and fetal physiology during pregnancy, and this chapter provides a more detailed overview of its role prior to and within gestation as well as disorders that arise from the dysregulation of these hormones.