Endocrine problems of adolescent pregnancy.

A number of changes in renal and endocrine physiology occur during pregnancy that alter hormone levels and affect a number of disease processes. Increased glomerular filtration causes an increase in hormone and substrate clearance. Increased placental steroid production causes an increase in hormone-binding globulin production, insulin resistance, and prolactinoma growth. Production of peptide hormones may cause changes in normal physiology and alter dynamic hormone testing. Placental vasopressinase increases vasopressin clearance. A number of diseases of hormone overproduction and underproduction affect pregnancy outcome and must be treated promptly by therapeutic modalities that also may affect the fetus.