Osmoregulatory adaptation in pregnancy and its disorders

Abstract

The physiological osmoregulatory adaptations of pregnancy include decreased thresholds for both thirst and AVP secretion and increased MCR for AVP. The combined effects of these changes may unmask subclinical DI. In view of the altered relationship between serum osmolality and thirst, caution is required in investigating thirst and polyuria in pregnancy lest an erroneous diagnosis of psychogenic polydipsia be made.