Arginine Vasopressin and Copeptin in Perinatology

Abstract

Arginine vasopressin (AVP) plays a major role in the homeostasis of fluid balance, vascular tonus, and the regulation of the endocrine stress response. The measurement of AVP levels is difficult due to its short half-life and laborious method of detection. Copeptin is a more stable peptide derived from the same precursor molecule, is released in an equimolar ratio to AVP, and has a very similar response to osmotic, hemodynamic, and stress-related stimuli. In fact, copeptin has been propagated as surrogate marker to indirectly determine circulating AVP concentrations in various conditions. Here, we present an overview of the current knowledge on AVP and copeptin in perinatology with a particular focus on the baby's transition from placenta to lung breathing. We performed a systematic review of the literature on fetal stress hormone levels, including norepinephrine, cortisol, AVP, and copeptin, in regard to birth stress. Finally, diagnostic and therapeutic options for copeptin measurement and AVP functions are discussed.

Keywords: HPA axis; antidiuretic hormone; asphyxia; cesarean section; neonate; pain; respiratory distress; stress.

Figure 1

Fold change of norepinephrine, cortisol, AVP, and copeptin between primary cesarean section and vaginal delivery. Study data were retrieved from the published literature and listed in chronologic order from oldest to newest on x-axis, corresponding references are given in Section “Surge in Fetal Stress Hormones” for all four hormones. The size of the diamonds reflects the study sample size: small corresponds to n = 0–50, middle n = 50–100, and large n = 100–170. Circles reflect the weighted mean values depending on sample size and are given at the final position of the x-axis.

Figure 2

Effects of AVP/ADH on various systems in the healthy and impaired newborn.